WO2020205850A1 - Method of preparing nanoparticles - Google Patents

Abstract

Disclosed is a method for preparing a nanoparticle composition. The method includes hydrogenating a hydrocarbon oil comprising a hydrocarbon having a carbon-carbon multiple bond, to give a hydrogenated hydrocarbon oil. The method further comprises forming a nanoparticle aerosol in a plasma reactor. The nanoparticle aerosol comprises MH-functional nanoparticles in a gas, where M is an independently selected Group IV element. The method also comprises collecting the MH-functional nanoparticles of the aerosol in a capture fluid comprising the hydrogenated hydrocarbon oil, thereby preparing the nanoparticle composition. A nanoparticle composition prepared in accordance with the method is also disclosed.

Description

METHOD OF PREPARING NANOPARTICLES

CROSS REFERENCE TO RELATED APPLICATION

[0001] The application claims priority to and all advantages of U.S. Provisional Patent Application No. 62/827,131 filed on 31 March 2019, the content of which is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The disclosure generally relates to methods for preparing nanoparticles and, more specifically, to methods of preparing silicon nanoparticle compositions utilizing passivated hydrocarbon-based capture fluids.

BACKGROUND

[0003] Nanoparticles are known in the art and can be prepared via various processes. Nanoparticles are often defined as particles having at least one dimension of less than 100 nanometers. Nanoparticles are produced either from a bulk material, which is initially larger than a nanoparticle, or from particles smaller than the nanoparticles, such as ions and/or atoms. Nanoparticles are particularly unique in that they may have significantly different properties than a bulk material or smaller particles from which the nanoparticles are derived. For example, a bulk material that acts as an insulator or semiconductor can be, when in nanoparticle form, electrically conductive or photoluminescent.

[0004] An important characteristic of nanoparticles (<100 nm diameter) is that they photoluminesce visible light when excited by electromagnetic radiation at an excitation wavelength. Nanoparticles may be used in various applications including in optoelectronics, diagnostics, analytics, and cosmetics. Nanoparticles have additional physical characteristics that differ from a bulk material, such as melting points that vary as a function of particle diameter.

[0005] Nanoparticles may be produced via a plasma process. For example, nanoparticles may be produced in a plasma reactor from a precursor gas. In certain plasma processes, the nanoparticles produced in the plasma reactor are captured or deposited in a capture fluid. In various applications, the nanoparticles may undergo further reactions with target functionalization compounds dispersed within the capture fluid, where the further reactions include surface functionalization reactions.

BRIEF SUMMARY OF THE INVENTION

[0006] The disclosure provides a method for preparing a nanoparticle composition. The method includes hydrogenating a hydrocarbon oil comprising a hydrocarbon having a carbon-carbon multiple bond, to give a hydrogenated hydrocarbon oil. The method further comprises forming a nanoparticle aerosol in a plasma reactor. The nanoparticle aerosol comprises MH-functional nanoparticles in a gas, where M is an independently selected Group IV element. The method also comprises collecting the MH-functional nanoparticles of the aerosol in a capture fluid comprising the hydrogenated hydrocarbon oil, thereby preparing the nanoparticle composition.

[0007] A nanoparticle composition prepared in accordance with the method is also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Other advantages of the present disclosure will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

[0009] Figure 1 illustrates one embodiment of a low pressure high frequency pulsed plasma reactor for producing nanoparticles;

[0010] Figure 2 illustrates an embodiment of a system including a low pressure pulsed plasma reactor to produce nanoparticles and a diffusion pump to collect the nanoparticles; and

[0011] Figure 3 illustrates a schematic view of one embodiment of a diffusion pump for collecting nanoparticles produced via a reactor.

DETAILED DESCRIPTION

[0012] The disclosure provides a method for preparing a nanoparticle composition. The method generally comprises forming an aerosol comprising nanoparticles in a gas, and collecting the nanoparticles from the aerosol in a passivated capture fluid. The method is particularly suitable for preparing compositions including nanoparticles produced via a plasma process. These features of the method, along with other general and specific features, are described in greater detail below.

[0013] The method comprises forming a nanoparticle aerosol in a plasma reactor.

[0014] The plasma reactor is not particularly limited, such that any plasma reactor, or systems comprising a plasma reactor, may be utilized to prepare the nanoparticle aerosol. In certain embodiments, the plasma reactor is a component of a plasma reactor system (alternatively referred to as a plasma system), which may be, e.g. a very high frequency low pressure plasma reactor system, a low pressure high frequency plasma reactor system, etc. Such plasma reactor systems are exemplified in Figure 1 , which shows a plasma reactor system generally at 20. The plasma reactor system 20 comprises a plasma generating chamber 22, a particle collection chamber 26 in fluid communication with the plasma generating chamber 22, and a vacuum source 28 in fluid communication with the particle collection chamber 26 and plasma generating chamber 22.

[0015] The plasma generating chamber 22, which may alternatively be referred to as a plasma reactor and/or as a discharge tube, comprises a high frequency (HF) or very high frequency (VHF) radio frequency (RF) power source (not shown). Power is supplied from the power source via the variable frequency RF power amplifier 21 that is triggered by an arbitrary function generator to establish a high frequency pulsed plasma (alternatively referred to simply as a plasma) in the area shown at 23. Typically, radiofrequency power is capacitively coupled into the plasma creating a capacitively coupled plasma discharge using a ring electrode, parallel plates, or an anode/cathode setup in the gas. Alternatively, the radiofrequency power may be inductively coupled into the plasma using an RF coil disposed around the discharge tube 22 in an inductively coupled plasma (ICP) reactor arrangement.

[0016] The plasma generating chamber 22 also comprises an electrode configuration 24 that is attached to a variable RF power amplifier 21. The plasma generating chamber 22 also comprises a second electrode configuration 25. The second electrode configuration 25 may be ground, DC biased, or operated in a push-pull manner relative to the electrode configuration 24. The plasma generating chamber 22 also includes a reactant gas inlet 29, and an outlet 30 that defines an aperture or orifice 31 . The plasma generating chamber 22 may also comprise a dielectric discharge tube (not shown). In various embodiments, the plasma generating chamber 22 comprises quartz.

[0017] In some embodiments, the electrode configurations 24, 25 for the plasma generating chamber 22 comprise a flow-through showerhead design, in which a VHF radio frequency biased upstream porous electrode plate 24 is separated from a downstream porous electrode plate 25, with the pores of the plates 24, 25 aligned with one another. The pores may be circular, rectangular, or any other desirable shape.

[0018] The particle collection chamber 26, which may alternatively be referred to as a deposition chamber and/or a vacuum particle collection chamber, generally contains a container 32.

[0019] The vacuum source 28 typically comprises a vacuum pump. In certain embodiments, however, the vacuum source 28 may comprise a mechanical, turbo molecular, diffusion, or cryogenic pump. During operation, portions of the plasma generating chamber 22 may be evacuated to a reduced pressure (i.e., a vacuum level), e.g. a pressure of from 1x1 O ⁷ to 500 Torr, alternatively of from 100 mT orr to 10 T orr.

[0020] In operation, the electrode configurations 24, 25 are used to couple the HF or VFIF power to a reactant gas mixture to ignite and sustain a glow discharge of plasma (i.e., “igniting a plasma”) within the area identified shown at 23. In certain embodiments, the reactant gas mixture, which may alternatively be referred to as a first reactive precursor gas, enters the dielectric discharge tube (not shown) where the plasma is generated. Regardless, molecular components of the reactant gas mixture are dissociated in the plasma as charged atoms, which nucleate to form nanoparticles from the reactant gas mixture and give an aerosol comprising the nanoparticles in the gas (i.e., a“nanoparticle aerosol”). This aerosol is then transported to the particle collection chamber 26 and, in particular, to the container 32.

[0021] More specifically, the particle collection chamber 26 generally comprises a capture fluid 27 that is disposed in the container 32 and used to capture nanoparticles. The container 32 or the capture fluid 27 may be adapted to be agitated (e.g. stirred, rotated, inverted, sonicated, etc.) (not shown), such as via a rotatable support, a stirring mechanism, etc. In some embodiments, the capture fluid 27 is agitated to refresh a surface of the capture fluid 27 and to force captured nanoparticles therein away from a centerline of the orifice 32. In this fashion, absorption rates of nanoparticles into the capture fluid 27 may be increased by increasing the agitation of the capture fluid 27. For example, in certain embodiments, ultrasonication may be utilized as an increased method of agitating the capture fluid 27. Typically, the capture fluid 27 is a liquid at the temperatures of operation of the plasma reactor system 20.

[0022] Generally, nanoparticles produced via the plasma reactor system 20 may be varied/controlled with respect to nanoparticle diameter by varying a distance between the aperture 31 in the outlet 30 of the plasma generating chamber 22 and the surface of the capture fluid 27 (i.e., the“collection distance”). The collection distance typically ranges from 5 to 50 times a diameter of the aperture 31 (i.e., from 5 to 50 “aperture diameters”). Positioning the surface of the capture fluid 27 too close to the aperture 31 may result in undesirable interactions of plasma with the capture fluid 27. Conversely, positioning the surface of the capture fluid 27 too far from the aperture 31 may reduce nanoparticle collection efficiency. As the collection distance is a function of the diameter of the aperture 31 and a pressure drop between the plasma generating chamber 22 and the collection chamber 26, an acceptable collection distance is typically from 1 cm to 20 cm, alternatively from 5 cm to 10 cm, alternatively from 6 cm to 12 cm, based on the operating conditions described herein.

[0023] In some embodiments, the HF or VHF radio frequency power source (not shown) operates at a preselected RF in a frequency range of 10 to 500 MHz to generate plasma for a time sufficient to form the nanoparticle aerosol. The preselected radio frequency may be a continuous frequency of from 10 to 500 MHz, alternatively of from 30 MHz to 150 MHz, and typically corresponds to a coupled power of from 5 to 1000 W, alternatively from 1 W to 200 W, respectively. In certain embodiments, the preselected radio frequency is a continuous frequency of from 100 to 150 MHz.

[0024] In some embodiments, the plasma generating chamber 22 may include an electrode 24 that is coupled to the VHF radio frequency power source and has a pointed tip (not shown) spaced apart by a variable distance from a grounded ring (not shown) inside the plasma generating chamber 22. The pointed tip can alternatively be positioned at a variable distance from a VHF radio frequency powered ring operated in a push-pull mode (180° out of phase). In some embodiments, the electrode configuration 24, 25 includes an inductive coil (not shown) coupled to the VHF radio frequency power source so that radio frequency power is delivered to the reactant gas mixture by an electric field formed by the inductive coil.

[0025] The plasma in area 23 is initiated (alternatively referred to as being ignited) via an RF power amplifier such as, for example, an AR Worldwide Model KAA2040, or an Electronics and Innovation Model 3200L, or an EM Power RF Systems, Inc. Model BBS2E3KUT. The amplifier can be driven (or pulsed) by an arbitrary function generator (e.g., a Tektronix AFG3252 function generator) that is capable of producing up to 200 watts of power from 0.15 to 150 MHz. In some embodiments, the arbitrary function may be able to drive the power amplifier with pulse trains, amplitude modulation, frequency modulation, or different waveforms. Power coupling between the amplifier and the reactant gas mixture typically increases as the frequency of the RF power increases. Driving power at a higher frequency may allow more efficient coupling between the power supply and discharge. Increased coupling may be manifested as a decrease in the voltage standing wave ratio (VSWR) according to formula 1 :

1 + p

VSWR = ^{l ~} P (1 ),

where p is the reflection coefficient:

Zp - Zc

p = Zc + Zp _{(2) ;}

where Zp and Zc representing the impedance of the plasma and coil respectively. At frequencies below 30 MHz, only 2-15% of the power is delivered to the plasma discharge, producing high reflected power in and RF circuit that leads to increased heating and limited lifetime of the power supply. In contrast, higher frequencies may be used to allow more power to be delivered to the plasma discharge, thereby reducing the amount of reflected power in the RF circuit.

[0026] In some embodiments, the power and frequency of the plasma discharge is preselected to create an optimal operating space for the formation of nanoparticles. Typically, tuning both power and frequency creates an appropriate ion and electron energy distribution in the plasma discharge to help dissociate the molecules of the reactant gas mixture and nucleate the nanoparticles. The power of the plasma discharge controls the temperature of individual particles within the plasma discharge. By controlling the temperature of individual particles within the plasma discharge, it is possible to control the crystallinity of the nanoparticles formed within the plasma discharge. Typically, higher power yields crystalline particles, while low power produces amorphous particles. Controlling both power and frequency may also be utilized to prevent the nanoparticles from growing too large.

[0027] The plasma reactor system 20 may be pulsed to directly manage the residence time for nanoparticle nucleation, and thereby control the particle size distribution and agglomeration kinetics in the plasma. In general, pulsing the system 20 allows for controlled tuning of the particle residence time in the plasma, which affects the size of the nanoparticles formed therein. By decreasing "on" time of the plasma, nucleating particles have less time to agglomerate, and therefore the size of the nanoparticles may be reduced on average (i.e., the nanoparticle distribution may be shifted to smaller diameter particle sizes). Likewise, a distance between the nanoparticle synthesis location and the surface of the capture fluid 27 is typically selected to be sufficiently short in order to avoid unwanted agglomeration of entrained nanoparticles.

[0028] The size distribution of the nanoparticles can also be controlled by controlling the plasma residence time, a high ion energy/density region of the VHF radio frequency low pressure glow discharge relative to a residence time of a precursor gas molecular through the discharge. Typically, at constant operating conditions (e.g. discharge drive frequency, drive amplitude, discharge tube pressure, chamber pressure, plasma power density, precursor mass flow rates, collection distance from plasma source electrodes, etc.) a lower plasma residence time of a VHF radio frequency low pressure glow discharge relative to the gas molecular residence time, corresponds to a decreased mean nanoparticle diameter at constant operating conditions. For example, as the plasma residence time of a VHF radio frequency low pressure glow discharge relative to the gas molecular residence time increases, the mean nanoparticle diameter follows an exponential growth model of the form y=yg - exp(-t_r/C), where y is the mean nanoparticle diameter, yg is the offset, t_r is the plasma residence time, and C is a constant. The particle size distribution may also be increased by increasing plasma residence time under otherwise constant operating conditions.

[0029] In some embodiments, the mean particle diameter of the nucleated nanoparticles (as well as the nanoparticle size distribution) can be controlled by controlling a mass flow rate of at least one precursor gas in a VHF radio frequency low pressure glow discharge. For example, as the mass flow rate of precursor gas (or gases) increases in the VHF radio frequency low pressure plasma discharge, the synthesized mean nanoparticle diameter may decrease following an exponential decay model of the form y=yg + exp(-MFR/C), where y is the mean nanoparticle diameter, yg is the offset, MFR is the precursor mass flow rate, and C’ is a constant, for constant operating conditions. Typical operating conditions may include discharge drive frequency, drive amplitude, discharge tube pressure, chamber pressure, plasma power density, gas molecule residence time through the plasma, and collection distance from plasma source electrodes. The synthesized mean nanoparticle size distribution may also decrease as an exponential decay model of the form y=yg + exp(-

MFR/K), where y is the mean nanoparticle diameter, ygis the offset, MFR is the precursor mass flow rate, and K is a constant, for constant operating conditions.

[0030] Typically, operating the plasma reactor system 20 at higher frequency ranges and pulsing the plasma provides the same conditions as conventional constricted/filament discharge techniques that use plasma instability to produce high ion energies/densities, but with the additional advantage that users can control operating conditions to select and produce nanoparticles predetermined sizes, which impacts certain characteristic physical properties (e.g. photoluminescence).

[0031] For a pulse injection, the synthesis (which may alternatively be referred to as deposition) of nanoparticles can be achieved using a pulsed energy source, such as a pulsed very high frequency RF plasma, a high frequency RF plasma, or a pulsed laser for pyrolysis. Typically, the VFIF radiofrequency is pulsed at a frequency ranging from 1 to 50 kHz.

[0032] As described above, the aerosol comprising the nanoparticles are transferred from the plasma reactor 22 to collection chamber 26 and, in particular, to the capture fluid 27 disposed in the container 32. In certain embodiments, the nanoparticles are transferred to the capture fluid 27 by pulsing input of the reactant gas mixture while the plasma is ignited. For example, in some such embodiments, the plasma is ignited with a first reactive precursor gas present to synthesize the nanoparticles, with at least one other gas present to sustain the discharge, such as an inert gas. The synthesis of the nanoparticles is stopped by stopping the flow of first reactive precursor gas (e.g. with a mass flow controller), and then resumed by flowing the first reactive precursor gas again. This pulsed stream technique can be used to increase the concentration of nanoparticles in the capture fluid 27, e.g. when the flux of functional nanoparticles impinging on the capture fluid 27 is greater than the absorption rate of the nanoparticles into the capture fluid 27. In certain embodiments, the nanoparticles are evacuated from the plasma reactor 22 to the particle collection chamber 26 (e.g. to the capture fluid 27 disposed in the container 32) by cycling the plasma to a low ion energy state and/or turning the plasma off.

[0033] In some embodiments, the nanoparticles are transferred from the plasma generating chamber 22 to the capture fluid 27 via a pressure differential between the plasma generating chamber 22 and the particle collection chamber 26, which can be controlled through a variety of means, and may be sufficient to create a supersonic jet of nanoparticles streaming out of the plasma generating chamber 22. The supersonic jet minimizes gas phase particle- to-particle interactions, thus keeping the nanoparticles monodispersed in the gas stream. In particular embodiments, the discharge tube 22 has an inside diameter that is much less than an inside diameter of the particle collection chamber 26, thus creating the pressure differential (e.g. where the pressure of the particle collection chamber 26 is less than the pressure of the reaction chamber 22). In various embodiments the pressure of the deposition chamber is < 1x10-^ Jorr, which may be controlled via the vacuum source 28. In some embodiments, the orifice 31 is adapted to force the plasma to reside partially inside the orifice 31 , e.g. based on Debye length of the plasma and size of the plasma generation chamber 22. In certain embodiments, orifice 31 may be varied electrostatically to develop a positive concentric charge that forces the negatively charged plasma through the aperture 31 .

[0034] As introduced above, upon the dissociation of molecules of the reactant gas mixture in the plasma generation chamber 22, nanoparticles form and are entrained in the gas phase. The distance between the nanoparticle synthesis location and the surface of capture fluid 27 must be short enough so that no unwanted nucleation or functionalization occurs while the nanoparticles are entrained in the gas phase, but instead the nanoparticles interact within the gas phase, and agglomerations of numerous, individual small nanoparticles form and are captured in the capture fluid 27. If too much interaction takes place within the gas phase, the nanoparticles may sinter together and form nanoparticles having larger average diameters.

[0035] Additional examples relating to reactors suitable for the present embodiments are described in the disclosures of International (PCT) Publication Nos. WO 2010/027959 and WO 201 1/109229, each of which is being incorporated herein by reference in its respective entirety. Such reactors can be, but are not limited to, low pressure high frequency pulsed plasma reactors.

[0036] It will be appreciated that other plasma reactors and plasma reactor systems may be utilized. For example, in certain embodiments, the method may be performed utilizing a plasma reactor system exemplified by the plasma reactor system shown generally at 50 in Figure 2. In these embodiments, the nanoparticles are prepared in the plasma reactor system 50, which, like the prior plasma reactor system described above, includes the plasma generation chamber 22.

[0037] In these embodiments, the plasma reactor system 50 includes a diffusion pump 120.

As such, the MX-functional nanoparticles can be collected by the diffusion pump 120. The particle collection chamber 26 may be in fluid communication with the plasma generating chamber 22. The diffusion pump 120 may be in fluid communication with the particle collection chamber 26 and the plasma generating chamber 22. In other forms of the present disclosure, the plasma reactor system 50 may exclude the particle collection chamber 26. For example, the outlet 30 may be coupled to an inlet 103 of the diffusion pump 120, or the diffusion pump 120 may be in substantially direct fluid communication with the plasma generating chamber 22.

[0038] Figure 3 is a cross-sectional schematic of an example diffusion pump 120 suitable for the plasma reactor system 50 of the embodiments of Figure 2. The diffusion pump 120 can include a chamber 101 having an inlet 103 and an outlet 105. The inlet 103 may have a diameter of 5 cm to 140 cm, and the outlet may have a diameter of 1 cm to 21 cm. The inlet 103 of the chamber 101 is in fluid communication with the outlet 30 of the reactor 20. The diffusion pump 120 may have, for example, a pumping speed of 65 to 65,000 liters/second or greater than 65,000 liters/second.

[0039] The diffusion pump 120 also includes a reservoir 107 in fluid communication with the chamber 101. The reservoir 107 supports or contains the capture fluid. The reservoir may have a volume of 30 ml to 15 liters. The volume of the capture fluid in the diffusion pump may be 30 ml to 15 liters. The diffusion pump 120 can further include a heater 109 for vaporizing the capture fluid in the reservoir 107. The heater 109 heats up the capture fluid and vaporizes the capture fluid to form a vapor (e.g., liquid to gas phase transformation). For example, the capture fluid may be heated to 100 to 400 °C, alternatively to 180 to 250 °C.

[0040] A jet assembly 1 1 1 can be in fluid communication with the reservoir 107 and the jet assembly 1 1 1 can comprise nozzles 1 13 for discharging the vaporized capture fluid into the chamber 101. The vaporized capture fluid flows and rises up though the jet assembly 1 1 1 and is emitted out the nozzles 1 13. The flow of the vaporized capture fluid is illustrated in Figure 3 using arrows. The vaporized capture fluid condenses and flows back to the reservoir 107. For example, the nozzle 1 13 can discharge the vaporized capture fluid against a wall of the chamber 101 . Walls of the chamber 101 may be cooled with a cooling system 1 14 such as a water cooled system. Cooled walls of the chamber 101 can cause the vaporized capture fluid to condense. The condensed capture fluid can then flow along and down the walls of the chamber 101 and back to the reservoir 107 under the force of gravity. The capture fluid can be continuously cycled through diffusion pump 120. The flow of the capture fluid causes gas that enters the inlet 103 to diffuse from the inlet 103 to the outlet 105 of the chamber 101. A vacuum source 33 may be in fluid communication with the outlet 105 of the chamber 101 to assist removal of the gas from the outlet 105.

[0041] As gas flows through the chamber 101 , nanoparticles entrained in the gas (e.g. the nanoparticles of the nanoparticle aerosol) can be absorbed by the capture fluid, which thereby collects the nanoparticles from the gas. For example, a surface of the nanoparticles may be wetted by the vaporized and/or condensed capture fluid. Agitating of cycled capture fluid may further improve absorption rate of the nanoparticles compared to a static fluid. The pressure within the chamber 101 may be less than 1 mTorr.

[0042] The capture fluid with the MX-functional nanoparticles can be removed from the diffusion pump 120. For example, the capture fluid with the MX-functional nanoparticles may be continuously removed and replaced with capture fluid that substantially does not include MX-functional nanoparticles.

[0043] Advantageously, the diffusion pump 120 can be used not only for collecting MX- functional nanoparticles but also for evacuating the plasma generating chamber 22 and collection chamber 26. For example, the operating pressure in the plasma generating chamber 22 can be a low pressure, e.g. less than atmospheric pressure, less than 760 Torr, or between 1 and 760 Torr. The collection chamber 26 can, for example, range from 1 to 5 milliTorr or have a pressure of less than 1x10-^ Torr. Other operating pressures are also contemplated.

[0044] The plasma reactor system 50 may also include the vacuum pump or vacuum source 33 in fluid communication with the outlet 105 of the diffusion pump 120. The vacuum source 33 can be selected in order for the diffusion pump 120 to operate properly. In one form of the present embodiment, the vacuum source 33 comprises the vacuum pump (e.g., auxiliary pump). The vacuum source 33 may comprise a mechanical, turbo molecular, or cryogenic pump. Flowever, other vacuum sources may alternatively, or additionally, be utilized.

[0045] In some embodiments, the method includes utilizing the plasma reactor system 50 of Figure 2 for forming a nanoparticle aerosol in the plasma generating chamber 22. The nanoparticle aerosol can comprise the nanoparticles in a gas, and the method further includes introducing the nanoparticle aerosol into the diffusion pump 120 from the plasma generating chamber 22. In such embodiments, the method also may include heating the capture fluid in the reservoir 107 to form a vapor, sending the vapor through the jet assembly 1 1 1 , emitting the vapor through nozzles 1 13 and into the chamber 101 of the diffusion pump 120, condensing the vapor to form a condensate, and flowing the condensate back to the reservoir 107. The method can also include capturing and collecting the nanoparticles of the nanoparticle aerosol in the capture fluid condensate in the reservoir 107. The action of capturing the nanoparticles of the nanoparticle aerosol in the capture fluid condensate may be identical to the action of collecting the nanoparticles of the nanoparticle aerosol in the capture fluid. The method can further include removing the gas from the diffusion pump 120 with the vacuum source 33. As compared to the embodiments described with reference to Figure 1 above, where the nanoparticles are collected directly in capture fluid 27, the plasma reactor system 50 utilizes a vaporized form of the capture fluid that is condensed in the diffusion pump 120 where it is utilized to capture/collected the nanoparticles from the nanoparticle aerosol. [0046] As introduced above, the nanoparticle aerosol formed in the plasma reactor comprises nanoparticles in a gas. With respect to the gas, one of skill in the art will readily appreciate that the gas comprises those gases introduced to the plasma reactor, such various gaseous components of the reactant gas mixture from which the nanoparticles are formed, which are described in detail below.

[0047] Regardless of the particular plasma reactor utilized, the nanoparticles formed in accordance with the embodiments of the method are MX-functional nanoparticles, where in each functional group represented by MX, M is an independently selected Group IV element (e.g. silicon, germanium, tin) and X is a functional group independently selected from H and halogen atoms (e.g. F, Cl, Br, and I). In certain embodiments, the MX-functional nanoparticles comprise at least one functional group MX where X is H. In such embodiments, the MX-functional nanoparticles may be designated as MH-functional nanoparticles. It will be appreciated, however, that the designation“MH-functional” denotes the presence of at least one MX functional group, as compared to the designation“MX- functional” which, as noted above, my comprise any number, or no, MH-functional groups. In general, the nanoparticle aerosol comprises MH-functional nanoparticles. In certain embodiments, the MH-functional nanoparticles further comprise MX-functionality, where M and X are as defined above.

[0048] In some embodiments, the nanoparticles comprise an alloy of Group IV elements, such as a silicon alloy (e.g. an alloy of silicon and carbide, germanium, boron, phosphorous, nitride, etc.).

[0049] As introduced above, the reactant gas mixture is utilized to produce the utilized to produce the nanoparticle aerosol, regardless of the particular plasma system and process selected. The reactant gas mixture generally comprises a precursor gas, which is utilized to from the MH-functional nanoparticles, but may also comprise additional components, such as any of those described herein.

[0050] The precursor gas is generally selected based on the desired composition of the nanoparticles. For example, as introduced above, the nanoparticle aerosol comprises MH- functional nanoparticles, which may also comprise MX-functionality. As such, the precursor gas generally comprises atoms for use as M (i.e., silicon, germanium, tin, and/or other Group IV elements), as well as H and halogen atoms suitable for X in the functional group represented by MX.

[0051] In certain embodiments, the precursor gas comprises silicon, which may be present or provided in the form of silicon compounds including silanes, disilanes, halogen-substituted silanes, halogen-substituted disilanes, C1 -C4 alkyl silanes, C1 -C4 alkyldisilanes, and the like, as well as derivatives and/or combinations thereof. For example, in some embodiments, the precursor gas comprises a silicon compound in an amount of from 0.1 to 2%, alternatively from 0.1 to 50% by volume of the precursor gas. In some such embodiments, the reactant gas mixture comprises the silicon compound in an amount of from 0.1 to 2%, alternatively from 0.1 to 50% by volume of the reactant gas mixture.

[0052] General examples of silicon compounds suitable for use in or as the precursor gas include alkylsilanes and aromatic silanes. Some specific examples of silicon compounds suitable for use in or as the precursor gas include dimethylsilane (H3C-SiH2-CH3), tetraethyl silane ((Ch^Ch^ Si) and diphenylsilane (Ph-SiH2-Ph)disilane (S^Hg), silicon tetrachloride (SiCl4), trichlorosilane (HSiCl3), dichlorosilane (h^SiC^). In particular embodiments, the silicon compound comprises SiCl4, HSiCl3, and/or h^SiC^.

[0053] In some embodiments, the precursor gas comprises germanium, which may be present or provided in the form of germanium compounds including germanes, digermanes, halogen-substituted germanes, halogen-substituted digermanes, C1 -C4 alkyl germanes, C-_| - C4 alkyldigermanes, and the like, as well as derivatives and/or combinations thereof.

Particular examples of germanium compounds suitable for use in or as the precursor gas include tetraethyl germane ((Ch^Ch^ Ge) and diphenylgermane (Ph-Geh^-Ph). The precursor gas may comprise both silicon and germanium, along with any other group IV elements.

[0054] In some embodiments, the precursor gas comprises an organometallic precursor compound comprising Group IV metal. Examples of such organometallic precursor compounds include organosilicon compounds, organogermanium compounds, and organotin compounds, such as alkylgermanium compounds, alkylsilane compounds, alkylstannane compounds, chlorosilane compounds, chlorogermanium compounds, chlorostannane compounds, aromatic silane compounds, aromatic germanium compounds, aromatic stannane compounds, and the like, as well as derivatives and/or combinations thereof. In these or other embodiments, the precursor has comprises a hydrogen gas, a halogen gas (e.g. a chlorine gas, a bromine gas, etc.), or both. In particular embodiments, the precursor gas comprises a compound comprising an atom of a Group IV element as well as H and/or halogen atoms.

[0055] Typically, the reactant gas mixture comprises the precursor gas in an amount of from 0.1 to 50, alternatively from 1 to 50, volume percent based on the total volume of the reactant gas mixture.

[0056] In some embodiments, e.g. where the nanoparticles are MX-functional and X comprises a halogen, the reactant gas mixture comprises a halogen gas (e.g. chlorine gas (CI2). The halogen gas may be present in the precursor gas, e.g. in a combined feed, or utilized as a separate feed along with or separate from the precursor gas. The relative amount of the halogen gas, if utilized, may be optimized based upon a variety of factors, such as the precursor gas selected, etc. For example, lesser amounts of the halogen gas may be required to prepare halogen-functional nanoparticles when the precursor gas comprises halogen atoms. In certain embodiments, the halogen gas is utilized in an amount of from greater than 0 to 25, alternatively from 1 to 25, alternatively from 1 to 10%, v/v of the total volume of the reactant gas mixture.

[0057] The reactant gas mixture may comprise other gases, i.e., aside from the precursor gas. In particular embodiments, the reactant gas mixture comprises an inert gas. The inert gas is generally non-reactive within any of the molecules or atoms present within the plasma stream during the operation of the plasma reactor. Examples of inert gasses include noble gases such as helium, neon, argon, krypton, xenon, and combinations thereof. When utilized, the inert gas is typically present in an amount of from 1 to 99 % v/v, based on the total volume of the reactant gas mixture.

[0058] The reactant gas mixture may comprise a dopant, e.g. a source of an atom to be integrated (i.e., “doped”) into the nanoparticles formed in the plasma reactor during the method. In such embodiments, the dopant may alternatively be referred to as a second precursor gas. In some embodiments, the nanoparticles undergo gas phase doping in the plasma, where the reactant gas mixture comprises a first precursor gas comprising silicon to form a silicon nanoparticle and a second precursor gas comprising another element, which is dissociated and is incorporated in the nanoparticles as they nucleate. Of course, the nanoparticles (i.e., once formed) may also or alternatively be doped, e.g. downstream of the production of the nanoparticles but prior to the nanoparticles being collected in the capture fluid. In some embodiments, the reactant gas mixture comprises a dopant comprising carbon, germanium, boron, phosphorous, and/or nitrogen, such as trimethylsilane, disilane, trisilane, BCI3, B2H0, PH3, GeH4, GeCl4, and the like, and combinations thereof. In certain embodiments, the reactant gas mixture comprises the dopant in an amount of from 0.1 to 49.9 % v/v based on total volume of the reactant gas mixture. In some embodiments, the reactant gas mixture comprises a combined amount of the precursor gas and the dopant of from 0.1 to 50 % v/v based on the total volume of the reactant gas mixture.

[0059] In particular embodiments, the reactant gas mixture comprises hydrogen gas. Typically, in such embodiments, the reactant gas mixture comprises hydrogen gas in an amount of from 1 to 50, alternatively from 1 to 2%, alternatively from 1 to 10%, by volume based on total volume of the reactant gas mixture.

[0060] The method comprises hydrogenating a hydrocarbon oil to give a hydrogenated hydrocarbon oil. The hydrogenated hydrocarbon oil is utilized in the method as a component or, or as, the capture fluid to collect the nanoparticles from the nanoparticle aerosol formed in the plasma reactor. In general, the hydrogenated hydrocarbon oil is prepared from the hydrocarbon oil to reduce and/or minimize the amount of carbon-carbon multiple bonds present in the capture fluid, as such carbon-carbon multiple bonds may detrimentally react with the MH-functionality of the MH-functional nanoparticles. For example, capture fluids are typically selected to be immiscible with the nanoparticles collected therein. However, MH- functional nanoparticles can react with carbon-carbon multiple bonds of hydrocarbons present in the capture fluid to give a hydrocarbon oil-miscible nanoparticle. Such miscibility is typically undesired on its own, but also represents a passivation of the nanoparticle due to the hydrocarbon pendent group that attaches to the nanoparticle from the hydrocarbons with the carbon-carbon multiple bonds that reacted therewith.

[0061] In general, the hydrocarbon oil comprises at least one unsaturated hydrocarbon, i.e., a hydrocarbon having at least one carbon-carbon multiple bond. The hydrocarbon oil may comprise a pure hydrocarbon composition, or may comprise a hybrid polymer, such as those comprising both hydrocarbon-based polymeric units and silicon-based polymeric units. For example, the hydrocarbon oil may comprise block polymers where the block polymers comprise silicone blocks and hydrocarbon blocks. In certain embodiments, the hydrocarbon oil comprises a polymerized alkylene (e.g. decene, undecene, dodecene, etc.) having residual unsaturation. Typically, the MH-functional nanoparticles are immiscible in the hydrocarbon oil, and the carbon-carbon multiple bonds of the hydrocarbon oil are reactive with the MH groups of the MH-functional nanoparticles to yield nanoparticles miscible with the hydrocarbon oil.

[0062] In certain embodiments, the hydrocarbon oil is a refined and/or processed hydrocarbon oil, e.g. has been processed to reduce the amount of carbon-carbon multiple bonds present therein (via previous hydrogenation and/or distillation). For example, in specific embodiments, the hydrocarbon oil is a previously-hydrogenated hydrocarbon oil, such that the method comprises hydrogenating the previously-hydrogenated hydrocarbon oil (which, prior to the hydrogenating, comprises residual carbon-carbon multiple bonds after the previously-hydrogenation). Generally, the hydrocarbon oil is immiscible with the nanoparticles to be collected in the capture fluid.

[0063] Hydrogenation of the hydrocarbon oil can be achieved by various processes for hydrogenation and/or reduction known in the art. Generally, hydrogenation of the hydrocarbon oil includes combining the hydrocarbon oil and a hydrogen source (e.g., hydrogen gas) in the presence of a hydrogenation catalyst. Suitable hydrogen sources for use in the hydrogenation include hydrogen gas and hydrogen donor molecules. Non-limiting examples of hydrogen donor molecules include formic acid, isopropanol, hydrazine, dihydronaphthalene, dihydroanthracene, and the like, as well as combinations thereof. When hydrogen donor molecules are used in a hydrogenation, the hydrogenation process may be referred to as a transfer hydrogenation. [0064] Examples of suitable hydrogenation catalysts include heterogeneous catalysts and homogenous catalysts. Heterogeneous catalysts are solids insoluble in the solvent comprising the unsaturated substrate. Suitable heterogeneous catalysts can include a fine powder support such as activated carbon, alumina, calcium carbonate, or barium sulfate. Specific examples of heterogeneous catalysts include nickel-based (e.g. Raney nickel/Ra- Ni), cobalt-based (e.g. Raney cobalt), palladium-based (e.g. palladium on carbon or Pd/C), and platinum-based (e.g. PtC>2 and platinum black) catalysts, and combinations thereof. Homogenous catalysts include those catalysts that dissolve in a solvent comprising an unsaturated substrate (i.e., a hydrocarbon oil including at least one carbon-carbon multiple bond), where the solvent may be the unsaturated substrate. Specific examples of homogenous catalysts include iridium-based (e.g. Crabtree’s catalyst), rhodium-based (e.g. [RhCI(COD)]2), ruthenium-based (e.g. the precatalyst dichlorotris(triphenylphosphine)ruthenium(ll)), and praseodymium-based (e.g. (S)-2-[2- (diphenylphosphino)phenyl]-4-isopropyl-4,5-dihydrooxazole) catalysts, and combinations thereof.

[0065] In various embodiments the hydrogenation catalyst can be selected to selectively hydrogenate particular unsaturated groups present in the hydrocarbon oil. For example, a catalyst may be selected to hydrogenate aliphatic carbon-carbon multiple bonds but not aromatic carbon-carbon multiple bonds.

[0066] Typically, hydrogenation requires a metal catalyst; however some hydrogen donor molecules can facilitate hydrogenation in the absence of a catalyst where these hydrogen donor molecules include diimide and aluminum isopropoxide.

[0067] Any reactor system may be used to facilitate the hydrogenation of the hydrocarbon oil. Examples of suitable reactor systems for this purpose include batch hydrogenation systems, flow hydrogenation systems, tubular plug-flow reactors, and gas liquid induction reactors (hydrogenators). In various embodiments, hydrogenation of a hydrocarbon oil includes agitating the hydrocarbon oil and/or bubbling hydrogen gas through the hydrocarbon oil.

[0068] In certain embodiments, the hydrogenated hydrocarbon oil comprises unsaturated groups in an amount of less than 5 parts per million based on a total number of carbon- carbon bonds in the hydrogenated hydrocarbon oil. In these or other embodiments, the hydrogenated hydrocarbon oil comprises unsaturated groups in an amount of less than 30% of the total number of MH functional groups of the MH-functional nanoparticles collected from the nanoparticle aerosol. In these or other embodiments, the hydrogenated hydrocarbon oil comprises a viscosity of from 5 to 200 centipoise at 25 °C. [0069] As introduced above, the nanoparticles of the nanoparticle aerosol formed in the plasma reactor are collected in the capture fluid. The capture fluid is selected to allow nanoparticles to be absorbed and dispersed therein as the nanoparticles are collected, thus forming a dispersion or suspension of nanoparticles in the capture fluid (i.e., a composition comprising the nanoparticles). In general, the capture fluid comprises, alternatively consists essentially of, the hydrogenated hydrocarbon oil prepared by hydrogenating the hydrocarbon oil.

[0070] In certain embodiments, the capture fluid comprises unsaturated groups in an amount of less than 5 parts per million based on a total number of carbon-carbon bonds in the capture fluid prior to collecting the MH-functional nanoparticles therein. In these or other embodiments, the capture fluid comprises unsaturated groups in an amount of less than 30% of the total number of MH functional groups of the MH-functional nanoparticles collected from the nanoparticle aerosol. Typically, the capture fluid comprises a viscosity of from 5 to 200 centipoise at 25 °C.

[0071] The capture fluid may have a dynamic viscosity of from 0.001 to 1 , alternatively of from 0.005 to 0.5, alternatively of from 0.01 to 0.1 Pa s at 23 ± 3 °C. Typically, the capture fluid comprises a viscosity of from 5 to 200 centipoise at 25 °C. Furthermore, the capture fluid may have a vapor pressure of less than 1 x 10 4 Torr. In some embodiments, curing collecting the nanoparticles from the nanoparticle aerosol, the capture fluid is at a temperature ranging from -20 °C to 150 °C and a pressure ranging from 1 to 5 milliTorr (0.133 Pa to 0.665 Pa). A low viscosity of the capture fluid is beneficial, if not necessary (e.g. when not agitating the capture fluid as described above), to allow the nanoparticles to be injected into and/or absorbed by the capture fluid in the plasma reactor without forming a film on the surface of the capture fluid surface. In some embodiments, the capture fluid may be used as a material handling and storage medium.

[0072] In addition to the hydrogenated hydrocarbon oil, the capture fluid may comprise other compounds, components, or fluids suitable for collecting the nanoparticles from the nanoparticle aerosol. For example, other components that may be utilized in the capture fluid include, silicone fluids, polar aprotic fluids, functionalization compounds, and others.

[0073] Specific examples of silicone fluids suitable for use in the capture fluid include polydimethylsiloxane, phenylmethyl-dimethyl cyclosiloxane, tetramethyltetraphenyltrisiloxane, and/or pentaphenyltrimethyltrisiloxane.

[0074] Suitable polar aprotic fluids (which may alternatively be referred to herein as an aprotic fluid) for use in the capture fluid, in various embodiments, have a viscosity at 25 °C of from 5 to 200 centiPoise (cP). Viscosity may be measured at 25 °C via a Brookfield LV DV-E viscometer, as understood in the art. The polar aprotic fluid may serve as a solvent or vehicle for the nanoparticles, as described in greater detail below. lUPAC defines“dipolar aprotic solvent” (alternatively referred to as polar aprotic fluids or polar aprotic fluids herein) as a solvent with a comparatively high relative permittivity (or dielectric constant), greater than around 15, and a sizable permanent dipole moment, that cannot donate suitable labile hydrogen atoms to form strong hydrogen bonds. Polar aprotic solvents are typically not strictly“aprotic” but, rather, protophilic (and, at most, weakly protogenic).

[0075] Examples of polar aprotic fluids suitable for use as the polar aprotic fluid include alkyl carbonates (e.g. ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate), esters (e.g. ethyl formate, methyl formate, methyl acetate, and ethyl acetate), cyclic ethers (e.g. 1 ,3-dioxolane, tetrahydrofuran, 2-methyltetrahydrofuran, and 2,5- dimethyltetrahydrofuran), lactones (e.g. valerolactone, and g-butyrolactone), aliphatic ethers (e.g. diethylether and 1 ,2-dimethoxyether), hexamethylphosphorous triamide (HMPT), hexamethylphosphoramide (HMPA), dichloromethane, N-methylpyrrolidone, alkylated alkylene glycols (e.g., mono- and di-alkyl polyalkylene glycols, including tetraethylene glycol dialkyl ethers such as tetra(ethylene glycol) dihexyl ether (DHTEG)), N-methylpyrrolidone, acetone, dimethylformamide (DMF), acetonitrile, dimethyl sulfoxide (DMSO), propylene carbonate (PC), dichloromethane, tetrahydrofuran (THF), acetonitrile, and various mixtures thereof.

[0076] In specific embodiments, the polar aprotic fluid comprises, alternatively is, a polyalkylene glycol dialkyl ether having the formula R²-[OCFl2CFl2]nOR², where each of R² and R² is an independently selected hydrocarbyl group and subscript n is >2. In some such embodiments, subscript n is 4 such that the polyalkylene glycol dialkyl ether is a tetraethylene glycol dialkyl ether. In these or other embodiments, each of R² and R² is an independently selected C5-C8 hydrocarbyl group. Examples of suitable C5-C8 hydrocarbyl groups include pentyl, hexyl, heptyl, and octyl groups. In some such embodiments, at least one of R² and R² is hexyl. In particular embodiments, both R² and R² are hexyl, such that the polar aprotic fluid comprises a tetraethylene glycol dihexyl ether.

[0077] In particular embodiments, the capture fluid comprises a functionalization compound that comprises a functional group Y reactive with the functional group X of the MX- functionality of the nanoparticles, if present. The capture fluid generally comprises the functionalization compound at the time the nanoparticles are collected in the capture fluid from the nanoparticle aerosol. In various embodiments, the functionalization compound is added to the capture fluid after collecting the nanoparticles.

[0078] The selection of the functionalization compound in general, and the functional group Y of the functionalization compound in particular, is based on the MX-functionality of the nanoparticles. For example, certain functional groups are reactive with hydrogen but not halogen atoms, whereas other functional groups are reactive with halogen atoms but not hydrogen. The functionalization compound is typically organic, i.e., the functionalization compound generally comprises carbon atoms.

[0079] In certain embodiments, the functional group X of the MX-functionality of the nanoparticles is H and the functional group Y of the unsaturated compound comprises an aliphatic carbon-carbon multiple bond. These embodiments, i.e., those involving MH- functionality where the functionalization compound comprises the unsaturated organic compound, are described immediately below.

[0080] The aliphatic carbon-carbon multiple bond of the unsaturated compound may be a double bond (C=C) or a triple bond (CºC). Further, the unsaturated organic compound may have more than one carbon-carbon multiple bond, with each carbon-carbon multiple bond being independently selected from a double bond and a triple bond. The aliphatic carbon- carbon multiple bond may be within a backbone of the unsaturated organic compound, pendent from the unsaturated organic compound, or at a terminal location of the unsaturated organic compound. For example, the unsaturated organic compound may be linear, branched, or partly branched, and the aliphatic carbon-carbon multiple bond may be located at any location of the unsaturated organic compound. Typically, the unsaturated organic compound is aliphatic, although the unsaturated organic compound may have a cyclic and/or aromatic portion, so long as the carbon-carbon multiple bond is located in an aliphatic portion of the unsaturated organic compound, i.e., the carbon-carbon multiple bond of the unsaturated organic compound is not present in, for example, an aryl group. In certain embodiments, the aliphatic carbon-carbon multiple bond is present at a terminal location of the unsaturated organic compound, i.e., the alpha carbon of the unsaturated organic compound is part of the carbon-carbon multiple bond. This embodiment generally reduces steric hindrance of the aliphatic carbon-carbon multiple bond for reasons described below.

[0081] In certain embodiments, the unsaturated organic compound may comprise or consist of carbon and hydrogen atoms. Alternatively, the unsaturated organic compound may be substituted or unsubstituted. By“substituted,” it is meant that one or more hydrogen atoms of the unsaturated organic compound may be replaced with atoms other than hydrogen (e.g. a halogen atom, such as chlorine, fluorine, bromine, etc.), or one or more carbon atoms within the chain of the unsaturated organic compound may be replaced with an atom other than carbon, i.e., the unsaturated organic compound may include one or more heteroatoms within the chain, such as oxygen, sulfur, nitrogen, etc.

[0082] Generally, the unsaturated organic compound includes at least 5, alternatively at least 10, alternatively at least 15, alternatively at least 20, alternatively at least 25, carbon atoms in its chain. Flowever, as described above, at least one carbon atom of the chain of the unsaturated organic compound may be substituted by an atom other than carbon, e.g. O. To this end, the values set forth above relative to the carbon atoms of the chain of the unsaturated compound also include any heteroatoms of the chain of the unsaturated compound.

[0083] For example, in various embodiments, the unsaturated organic compound may comprise an ester having the carbon-carbon multiple bond. In this embodiment, at least one carbon atom of the chain of the unsaturated organic compound is replaced by an oxygen atom so as to form an ether linkage with a carbonyl group adjacent thereto. In this embodiment, the unsaturated organic compound is typically a ³C-_| Q ester. Specific examples of such esters suitable for the purposes of the unsaturated organic compound include, but are not limited to, allyl dodecanoate, dodecyl 3-butenoate, propyl 10-undecenoate, 10- undecenyl acetate, and dodecyl (meth)acrylate.

[0084] In other embodiments, the functional group X of the MX-functional nanoparticles is the independently selected halogen atom and the functional group Y of the functionalization compound is reactive with the MX-functionality of the nanoparticles. In such embodiments, specific examples of the functionalization compound include an alcohol compound such as methanol, ethanol, 1 -propanol, 2-propanol, n-butanol, sec-butanol, iso-butanol, tert-butanol, n-hexanol, n-octanol, n-decanol; a thiol compound such as methanethiol, ethanethiol, 1 - propanethiol, 2-propanethiol, n-butanethiol, sec-butanethiol, iso-butanethiol, tert-butanethiol, n-hexanethiol, n-octanethiol, n-decanethiol; an amine compound such as methylamine, dimethylamine, ethylamine, diethylamine, phenylamine, diphenylamine; a carboxylic acid compound such as acetic acid, propanoic acid, butanoic acid, hexanoic acid, octanoic acid, decanoic acid, benzanoic acid; a sulphide compound such as hydrogen sulfide; an amide compound such as acetamide, propanamide, butanamide, hexanamide, octanamide, decanamide, benzamide; a phosphine compound such as methylphosphine, dimethylphosphine, ethylphosphine, diethylphosphine, phenylphosphine, diphenylphosphine; a metal halide compound such as lithium fluoride, lithium chloride, lithium bromide, sodium fluoride, sodium chloride, sodium bromide, potassium fluoride, potassium chloride, potassium bromide; a terminal alkyne compound such as acetylene, propyne, but-1 -yne, hex-1 -yne, oct-1 -yne, phenylacetylene; an organometallic compound, an alkali metal amide compound such as lithium amide, lithium methylamide, lithium dimethylamide, diisopropylamide; a metal thiolate compound such as lithium methanethiolate, sodium methanethiolate, potassium methanethiolate, lithium ethanethiolate, sodium ethanethiolate, potassium ethanethiolate, lithium phenylthiolate sodium phenylthiolate, potassium phenylthiolate; and combinations thereof. Specific examples of organometallic compounds include, but are not limited to, metal alkoxide compounds such as lithium methoxide, sodium methoxide, potassium methoxide, lithium ethoxide, sodium ethoxide, potassium ethoxide, lithium phenoxide, sodium phenoxide, potassium phenoxide; Grignard reagents such as methyl magnesium chloride, methyl magnesium bromide, ethyl magnesium chloride, ethyl magnesium bromide, phenyl magnesium chloride, phenyl magnesium bromide; organozinc reagents such as dimethyl zinc, diethyl zinc, diphenyl zinc, methylzinc chloride, methylzinc bromide, ethylzinc chloride, ethylzinc bromide, phenylzinc chloride, phenylzinc bromide; Gilman reagents such as lithium dimethylcuprate lithium diethylcuprate, lithium diphenylcuprate; organosodium reagents such as methylsodium, ethylsodium, phenylsodium; organopotassium reagents such as methylpotassium, ethylpotassium, phenylpotassium; organocalcium reagents such as methylcalcium iodide, diphenylcalcium, dibenzylcalcium; organolithium reagents such as methyllithium, ethyllithium, phenyllithium; and combinations thereof.

[0085] In various embodiments, functional group Y of the functionalization compound is a nucleophilic functional group reactive with the MX-functionality of the nanoparticles. In such embodiments, the functionalization compound may be an alcohol compound, a thiol compound, a cyanate compound, an amine compound, an azide compound, a nitrile compound, a carboxylic acid compound, a sulfide compound, an amide compound, a phosphine compound, a metal halide compound, a terminal alkyne compound, an organometallic compound, an alkali metal amide compound, a metal thiolate compound, or combinations thereof. It will be appreciated that reference to the functionalization compound being an “alcohol compound”, a “thiol compound,” etc. refers to the functionalization compound comprising a particular functional group (e.g. an alcohol and/or thiol functional group, for example), which typically composes the functional group Y.

[0086] Each of the specific examples of the functionalization compounds listed above includes a functional group Y that is reactive with the MX-functionality of the nanoparticles, when present. As in embodiments where the functionalization compound comprises the unsaturated organic compound, the functional group Y may be located at any location within the functionalization compound, but is typically terminal, e.g. bonded to an alpha carbon of the functionalization compound. Some of the specific examples of the functionalization compounds set forth above may be complexes, e.g. including ligands. There are no specific limitations with respect to the functionalization compound so long as the functionalization compound is reactive with the MX-functionality of the nanoparticles, when present.

[0087] If desired, the functionalization compound may include additional functionality (i.e., functionality other than and in addition to the functional group Y). For example, in certain embodiments, the functionalization compound further comprises at least one functional group Z in addition to the functional group Y, with the functional group Z being convertible to a hydrophilic functional group. In various embodiments, the functionalization compound may be a hydrophilic or polar (i.e., the functionalization compound includes hydrophilic or polar moieties) and not include any functional group Z convertible to a hydrophilic functional group. When a functionalization compound includes a Z group or the functionalization compound is hydrophilic or polar, the functionalization compound may be referred to as a polar pendant precursor or as a hydrophilic pendant precursor where the word“precursor” may be understood to alternatively (depending upon the nature of a particular functionalization compound) modify either the word“pendant” alone or the phrases“polar pendant” and“hydrophilic pendant,” respectively.

[0088] When referring to the functional group Z as being convertible, it is to be understood that the word“convertible” is used to indicate that the functional group Z may undergo a chemical reaction to yield a hydrophilic functional group having a comparatively greater hydrophilicity than the functional group Z species prior to being subjected to the chemical reaction. The functional group Z may, in certain embodiments, be selected from some of the functional groups set forth above suitable for the functional group Y, although in such embodiments, the functional group Z is separate from and in addition to the functional group Y in the functionalization compound. In various embodiments, the functional group Z may be converted to a hydrophilic or polar functional group by being put in contact with and reacted with a deprotection compound, such as tetrafluoro acetate (TFA).

[0089] A specific example of a conversion is a deprotection reaction, which is readily understood in the art as removing a protecting group from an otherwise reactive functional group. For example, in particular embodiments, the functionalization compound comprises a protected functional group, such as a trialkylsilyl ether group, a ketal group, etc., which may be readily converted to an unprotected functional group, such as, in this example, an alcohol or diol, respectively. Such protected functional groups may be utilized to prevent undesired reaction during the method, to influence the solubility and/or reactivity of the functionalization compound, to influence the purification of any of the reaction products of the method, or combinations thereof.

[0090] Specific examples of hydrophilic functional groups include carboxylic acid functional groups, alcohol functional groups, hydroxy functional groups, azide functional groups, silyl ether functional groups, ether functional groups, phosphonate functional groups, sulfonate functional groups, thiol functional groups, amine functional groups, anhydride functional groups, and combinations thereof. The amine functional group may be primary, secondary, tertiary, or cyclic. Such hydrophilic functional groups may be bonded directly to a chain of the functionalization compound, e.g. to a carbon atom of the chain, or may be bonded via a heteroatom or bivalent linking group. In various embodiments, the functionalization compound comprises a hydrophilic functional group different from Y in addition to functional group Z or in the absence of any functional group Z.

[0091] In certain embodiments, the functionalization compound may include the hydrophilic functional group, such as any of the hydrophilic functional groups set forth above. Alternatively, the functionalization compound may include the at least one functional group Z convertible to a hydrophilic functional group such that the functionalization compound does not include a hydrophilic functional group until the at least one functional group Z is converted thereto. Specific examples of the at least one functional group Z convertible to a hydrophilic functional group include, but are not limited to: ester functional groups, including those of oxo acids, such as esters of carboxylic acid, sulfuric acid, phosphoric acid, nitric acid, and boric acid; acid halide functional groups; amide functional groups; nitrile functional groups; disulfide functional groups; epoxide functional groups; silyl ether functional groups; ethylenically unsaturated groups in addition to the aliphatic carbon-carbon multiple bond; oxazoline functional groups; and anhydride functional groups. Esters of oxo acids may be derived from condensation of any alcohol with a particular oxo acid where the alcohol may be aliphatic or aromatic. The at least one functional group Z may be a substituent of the functionalization compound or a moiety within the functionalization compound. For example, when the functionalization compound includes an ester functional group, the ester functional group is generally a moiety within the functionalization compound, as opposed to a substituent bonded thereto.

[0092] The at least one functional group Z of the functionalization compound is generally selected based on the MX-functionality of the nanoparticles as well as the functional group Y of the functionalization compound. For example, when X is FI, reacting X and Y results in Si- C bonds. In contrast, when X is an independently selected halogen atom, reacting X with Y may result in SiC bonds, Si-O-C bonds, and/or Si-N-C bonds. Because Si-O-C bonds, and/or Si-N-C bonds may hydrolyze, further reaction to form the hydrophilic functional group is generally not carried out in an aqueous medium. In these embodiments, the functionalization compound may further comprise a butoxycarbonyl group.

[0093] The capture fluid generally comprises the functionalization compound, when present, in an amount sufficient to provide a molar ratio of the functional group Y to MX-functional groups of the nanoparticles of at least 1 :1 , alternatively at least 1.2:1 , alternatively at least 1 .4:1. Molar ratios much higher than 1 .4:1 may advantageously be utilized. In various embodiments, the capture fluid comprises the functionalization compound in an amount of from greater than 0 to 100, alternatively from greater than 0 to 50, alternatively from 1 to 40, alternatively from 2 to 30, alternatively from 5 to 15, percent by weight based on total weight of the capture fluid. The balance of the capture fluid may comprise any of the components set forth herein, although the balance of the capture fluid typically comprises hydrocarbons for miscibility with the functionalization compound and immiscibility with the nanoparticles.

[0094] As introduced above, the method may further comprises reacting the MX-functionality of the nanoparticles with the functionalization compound to form a composition comprising functionalized nanoparticles. The reaction of the MX-functionality and the functionalization compound may comprise any functionalization reaction, such as those described herein with respect to the exemplary groups of MX and Y.

[0095] In certain embodiments, particularly when X is H and the functionalization compound comprises the unsaturated organic compound, reacting the MX-functionality of the nanoparticles with the unsaturated organic compound comprises irradiating a suspension of the MH-functional nanoparticles in the capture fluid with UV radiation. For example, reacting the MH-functional nanoparticles with the unsaturated organic compound may be photoinitiated. When reacting the MH-functional nanoparticles and the unsaturated organic compound comprises irradiating the suspension of the MH-functional nanoparticles in the capture fluid with radiation, the radiation is typically electromagnetic radiation having a wavelength of from 10 to 400, alternatively 280 to 320, nm.

[0096] Alternatively or in addition to radiation, reacting the MX-functionality of the nanoparticles with the functionalization compound may comprise heating a suspension of the MX-functionality of the nanoparticles and the capture fluid to or at a first temperature for a first period of time. When heat is utilized to react the MX-functional nanoparticles with the functionalization compound, the first temperature is typically from 50 to 250 °C and the first period of time is from 5 to 500 minutes.

[0097] Alternatively still, the MX-functionality of the nanoparticles may react with the functionalization compound once the nanoparticles are collected in the capture fluid such that no reaction condition (e.g. irradiation or heat) is utilized or applied. However, heat or irradiation generally improves a reaction between the MX-functionality of the nanoparticles and the functionalization compound. Functionalization of the nanoparticles may improve physical properties of a resulting nanoparticle composition, including photoluminescence and photoluminescent intensity.

[0098] If desired, a catalyst or photocatalyst may be utilized during an action of reacting the MX-functionality of the nanoparticles with the functionalization compound. Such catalysts are well known in the art based on a desired reaction mechanism, e.g. when X is H, any catalysts suitable for hydrosilylation may be utilized, which are typically based on precious metals, e.g. platinum. However, catalysts or photocatalysts are not required for the action of reacting the MX-functional nanoparticles with the functionalization compound.

[0099] When the functionalization compound includes the at least one functional group Z convertible to a hydrophilic functional group, the method may further comprise the step of converting the functional group Z to a hydrophilic functional group. The functional group Z of the compound may be converted to a hydrophilic functional group before, during, and/or after reacting the nanoparticles with the functionalization compound. Typically, the functional group Z of the functionalization compound is converted to a hydrophilic functional group after reacting the nanoparticles and the functionalization compound. [00100] The functional group Z of the functionalization compound may be converted to a hydrophilic functional group via known methods. In various embodiments, converting the functional group Z of the functionalization compound to a hydrophilic functional group comprises hydrolyzing the functional group Z.

[00101] In various embodiments, the functional group Z of the functionalization compound may be converted to a hydrophilic functional group by acidic or basic treatment. In these embodiments, an acid or base utilized is generally selected such that the acid or base is miscible with the capture fluid. Further, the acid is typically selected such that it can be removed from the capture fluid, e.g. by vacuum or washing with solvent. To this end, the acid may be selected from trifluoroacetic acid, hydrofluoric acid, and combinations thereof. The acid may be utilized in various concentrations in an aqueous form.

[00102] In one specific embodiment, the nanoparticles are collected in the capture fluid, and the nanoparticles and the functionalization compound are reacted in the capture fluid. After reacting the nanoparticles and the functionalization compound, nanoparticles result which have a substituent formed from the functionalization compound. If the functionalization compound further includes the functional group Z convertible to a hydrophilic functional group, the functional group Z is present in the substituent of the nanoparticles. To this end, if the functionalization compound further includes the functional group Z convertible to a hydrophilic functional group, the method may further comprise converting the functional group Z to a hydrophilic group. An aqueous acid may be disposed in the capture fluid to convert the functional group Z to a hydrophilic functional group, optionally at a reflux temperature of the capture fluid including the aqueous acid. After converting the functional group Z to a hydrophilic functional group, the substituent of the nanoparticles includes a hydrophilic functional group.

[00103] In various embodiments, the method further comprises separating the nanoparticles and the capture fluid to form separated nanoparticles. For example, the nanoparticles and the capture fluid may be separated by centrifuging and/or decanting to yield separated nanoparticles. The separated nanoparticles may be further washed by suspension in a solvent, e.g. toluene or hexane, followed by repeated separation from the solvent by centrifuging and/or decanting. The separated nanoparticles may ultimately be dried, e.g. in vacuo, to form a dried solid. In various embodiments, the separated nanoparticles are a solid. In this embodiment, the separated nanoparticles are free-standing and not in solution or suspension. The separated nanoparticles may be utilized in various end uses and applications.

[00104] Further, when the compound includes the functional group Z convertible to a hydrophilic functional group, and when the method further comprises converting the functional group to a hydrophilic functional group, the separated nanoparticles may advantageously be suspended in a polar solvent, which offers significant advantages. For example, the method may further comprise suspending the separated nanoparticles in a polar solvent, such as an aqueous solution, optionally along with ions, e.g. from disassociated sodium bicarbonate. The polar solvent may be selected from water and a dipolar aprotic organic solvent.

[00105] After reacting the nanoparticles with the functionalization compound, nanoparticles result which have a substituent, which is typically organic and is formed from the functionalization compound. For example, the functionalization compound is generally covalently bonded to the nanoparticles, e.g. as a ligand or substituent. The nanoparticles are generally no longer MX-functional, and thus the nanoparticles have increased stability in solution or suspension. A suspension comprising the nanoparticles in the capture fluid is generally referred to as a nanoparticle composition. The disclosure also provides the nanoparticle composition formed in accordance with the method.

[00106] The nanoparticles and nanoparticle compositions can be prepared by any of the methods described above. Any of various compositions may comprise the MFI-functional nanoparticles or functionalized nanoparticles; for example, a cosmetic composition, or a composition comprising nanoparticles or nanoparticles dispersed in a carrier fluid. Contingent on the precursor gas and molecules utilized in the plasma process, nanoparticles of various composition may be produced. The description below refers to the nanoparticles generally, which is applicable to both the MFI-functional nanoparticles, as well as the nanoparticles of the nanoparticle composition formed by reacting the MX-functionality of the nanoparticles and the functionalization compound.

[00107] The nanoparticles may exhibit a number of unique electronic, magnetic, catalytic, physical, optoelectronic and optical properties due to quantum confinement effects. For example, many semiconductor nanoparticles exhibit photoluminescence effects that are significantly greater than the photoluminescence effects of macroscopic materials of similar composition.

[00108] A diameter of the nanoparticles can be calculated from the following equation:

[00109] As set forth in Proot, et. al. Appl. Phys. Lett., 61 , 1948 (1992); Delerue, et.al. Phys. Rev. B., 48, 1 1024 (1993); and Ledoux, et. al. Phys. Rev. B., 62, 15942 (2000), where h is Plank’s constant, c is the speed of light, and Eg is the bulk band gap of silicon.

[00110] The functionalized nanoparticles and/or the nanoparticles may independently have a largest dimension or average largest dimension less than 50, alternatively less than 20, alternatively less than 10, alternatively less than 5 nm. Optionally the nanoparticles include a largest dimension of greater than 0.1 nm. Furthermore, the largest dimension or average largest dimension of the nanoparticles may be between 1 and 50, alternatively between 2 and 50, alternatively between 2 and 20, alternatively between 2 and 10, alternatively between 2.2 and 4.7 nm. The largest dimension of the nanoparticles can be measured by a variety of methods, such as with a transmission electron microscope (TEM). For example, as understood in the art, particle size distributions are often calculated via TEM image analysis of hundreds of different nanoparticles. In various embodiments, the nanoparticles may comprise quantum dots, typically silicon quantum dots. Quantum dots have excitons confined in all three spatial dimensions and may comprise individual crystals, i.e., each quantum dot is a single crystal.

[00111] In various embodiments, the nanoparticles may be photoluminescent when excited by exposure to UV light. Depending on the average diameter of the nanoparticles, the nanoparticles may photoluminescence in any of the wavelengths in the visible spectrum and may visually appear to be red, orange, green, blue, violet, or any other color in the visible spectrum. For example, when the nanoparticles have an average diameter of less than 5 nm, visible photoluminescence may be observed, and when the nanoparticles have an average diameter less than 10 nm near infrared (IR) luminescence may be observed. In one form of the present disclosure, the nanoparticles have a photoluminescent intensity of at least 1 x 10⁶ at an excitation wavelength of 365 nm. The photoluminescent intensity may be measured with a Fluorolog3 spectrofluorometer (commercially available from Horiba of Edison, NJ) with a 450 W Xe excitation source, excitation monochromator, sample holder, edge band filter (400 nm), emission monochromator, and a silicon detector photomultiplier tube. To measure photoluminescent intensity, the excitation and emission slit width are set to 2 nm and the integration time is set to 0.1 s. In these or other embodiments, the silicon nanoparticles may have a quantum efficiency of at least 4% at an excitation wavelength of 395 nm as measured on an FIR400 spectrophotometer (commercially available from Ocean Optics of Dunedin, Florida) via a 1000 micron optical fiber coupled to an integrating sphere and the spectrophotometer with an absorption of >10% of the incident photons. Quantum efficiency is calculated by placing a sample into the integrating sphere and exciting the sample via a 395 nm LED driven by an Ocean Optics LED driver. The system was calibrated with a known lamp source to measure absolute irradiance from the integrating sphere. The quantum efficiency is then calculated by the ratio of total photons emitted by the nanoparticles to the total photons absorbed by the nanoparticles. Further, in these or other embodiments, the nanoparticles may have a full width at half maximum emission of from 20 to 250 at an excitation wavelength of 270-500 nm. [00112] Without wishing to be bound to a particular theory, photoluminescence of the silicon nanoparticles is thought to be caused by a quantum confinement effect that occurs when the diameter of the silicon nanoparticles is smaller than the excitation radius, which results in bandgap bending (i.e., increasing of the gap). The bandgap energy of a nanoparticle changes as a function of the diameter of the nanoparticle. Although silicon is an indirect bandgap semiconductor in bulk, silicon nanoparticles with diameters of less than 5 nm emulate a direct bandgap material, which is made possible by interface trapping of excitons.

Furthermore, both the photoluminescent intensity and luminescent quantum efficiency may continue to increase over time, particularly when the nanoparticles are exposed to air to passivate surfaces of the nanoparticles. In another form of the present disclosure, the maximum emission wavelength of the nanoparticles shifts to shorter wavelengths (i.e., a blue-shift of an emission spectrum) over time when passivated (e.g., being exposed to oxygen). The luminescent quantum efficiency of the nanoparticles may be increased by 200% to 2500% upon passivation. However, other increases in the luminescent quantum efficiency are also contemplated. The photoluminescent intensity may increase from 400 to 4500% depending on time extent of passivation and concentration of the nanoparticles in a fluid in which they are suspended. However, other increases in the photoluminescent intensity are also contemplated. The wavelength spectrum for light emitted from the nanoparticles experiences a blue shift with passivation of the nanoparticles. In one form of the present disclosure, a maximum emission wavelength undergoes a blue-shift of 100 nm, corresponding to an approximately 1 nm decrease in nanoparticle size, depending on time duration of passivation. However, other maximum emission wavelength shifts are also contemplated herein. Alternative means of passivation include contacting the silicon nanoparticles with a nitrogen-containing gas such as ammonia to create a surface layer on the silicon nanoparticles where the surface layer comprises nitride.

EXAMPLES

[00113] The following examples, illustrating the compositions and methods of this disclosure, are intended to illustrate and not to limit the disclosure.

Example 1 : Preparation of MX-functional nanoparticles

[00114] Silicon nanoparticles are synthesized from a very high frequency (VHF) low pressure plasma system. Ultra-high purity precursor gases (Ar, H2, S1H4, and CI2) are introduced into a quartz discharge tube (the reaction chamber) via mass flow controllers at a specific ratio and pressure. Typical pressures within the quartz discharge tube are from 1 to 5 Torr.

[00115] The gases are then dissociated via a very high frequency plasma discharge (100-

150 MHz) to ignite a plasma. The VHF is chosen to maximize plasma coupling while minimizing drive amplitude of a function generator that provides a sinusoidal signal to a Class A radio frequency amplifier.

[00116] Silicon atoms coalesce, nucleate, and grow to form silicon nanocrystals (alternatively referred to as silicon nanoparticles) in the plasma discharge. The power of the plasma discharge controls the temperature of individual silicon nanocrystals to allow for control of crystallinity of the silicon nanocrystals. Higher power yields crystalline silicon nanocrystals, while lower power produces amorphous silicon nanocrystals.

[00117] Concentration of silicon atoms and residence time of silicon atoms within the plasma discharge (plasma residence time) control the size of the silicon nanoparticles. Once the silicon nanoparticles leave the plasma discharge, via the orifice located at the bottom of the quartz discharge tube (alternatively referred to as a quartz plasma chamber), the silicon nanoparticles no longer grow.

[00118] The silicon nanoparticles exit the plasma discharge with SiH_x (x<4), radicals (dangling bonds), and/or halogen species (if present in the quartz discharge tube) on the surface of the nanoparticles. The silicon nanoparticles exit through the orifice driven by a large pressure drop into the deposition chamber. The pressure of the deposition chamber is <1x10 5 Torr (produced by a high vacuum pump, e.g. a turbo-molecular, cryogenic, or diffusion pump). The large pressure drop creates a supersonic jet of particles streaming out of the plasma chamber. The supersonic jet minimizes any interactions between gas- entrained silicon nanoparticles, thus keeping the silicon nanoparticles monodispersed in a gas stream.

[00119] An agitated capture fluid (a low viscosity liquid having a viscosity of less than 0.2 Pa-s) is disposed in a cup and is used to capture the silicon nanoparticles at a low pressure (<1 x10 5 Torr) in the deposition chamber. The location of a surface of the capture fluid is located within a distance of the orifice sufficient to ensure that the silicon nanoparticles remain dispersed in a supersonic jet of gas prior to being deposited within the capture fluid. The capture fluid has a low viscosity to allow the silicon nanoparticles to be deposited or injected into the capture fluid without forming a film on the surface of the capture fluid. Agitation of the capture fluid is used to refresh the surface of the capture fluid and force silicon nanoparticles deposited within the capture fluid away from a centerline of the orifice.

[00120] The capture fluid and silicon nanoparticles dispersed therein are placed into a temperature-humidity oven (typically 60 °C and 85% relative humidity) for 24 hours to passivate surfaces of the particles with a diffusion-limited oxide (SiO_x, x>2). This passivation blue-shifts emission spectra and increases the photoluminescent intensity.

[00121] Once the silicon nanoparticles are deposited in (i.e., absorbed by) the capture fluid, the capture fluid with the silicon nanoparticles dispersed therein (i.e., the sample) is removed from the deposition chamber and a photoluminescence spectrum is measured. This measurement is performed using a Horiba FL3 spectrofluorometer with a 450 watt Xenon source. An excitation monochromator is set to 365 nm with a slit width of 2 nm. A 400 nm edge filter is placed in a beam path leading to an emission monochromator, downstream of the sample.

Example 2: Preparation of Capture Fluid Comprising a Hydrogenated Hydrocarbon Oil

[00122] Catalyst 1 is added to a reaction vessel containing Hydrocarbon Oil 1 at a concentration of approximately 1 % by mass to prepare a mixture. Forming gas (-3-10 vol% H2) is bubbled through the mixture with stirring overnight at room temperature to give a reaction mixture comprising a hydrogenated hydrocarbon oil. The reaction mixture is filtered to remove solids to give a capture fluid comprising a hydrogenated hydrocarbon oil.

[00123] Catalyst 1 is Palladium on carbon (Pd/C).

[00124] Hydrocarbon Oil 1 is a hydrogenated decene homopolymer of general formula [CH₂CH[(CH₂)₇CH₃]]_n.

Example 3: Preparation of a Nanoparticle Composition with a Capture Fluid Comprising a Hydrogenated Hydrocarbon Oil

[00125] The capture fluid comprising the hydrogenated hydrocarbon oil prepared according to Example 2 is used to prepare silicon nanoparticles according to the procedure of Example 1. The resulting nanoparticle composition is a hazy/cloudy suspension, and the silicon nanoparticles exhibit settling over the course of a few hours.

[00126] These observations are consistent with the capture fluid comprising the hydrogenated hydrocarbon oil including unsaturation at a concentration low enough to prevent functionalization of surfaces of silicon nanoparticles, resulting in the silicon nanoparticles being immiscible in the capture fluid.

Comparative Example 1 : Preparation of a Nanoparticle Composition with a Capture Fluid Comprising a Hydrocarbon Oil

[00127] Hydrocarbon Oil 1 (a hydrogenated decene homopolymer of general formula [CH₂CH[(CH₂)7CH3]]_n) is utilized as a capture fluid to prepare silicon nanoparticles according to the procedure of Example 1. The resulting nanoparticle composition is a clear dispersion.

[00128] These observations are consistent with Hydrocarbon Oil 1 including residual/contaminating unsaturation at concentrations capable of reacting with surface sites of silicon nanoparticles, to render the silicon nanoparticles miscible with the Hydrocarbon Oil 1 .

[00129] The terms“comprising” or“comprise” are used herein in their broadest sense to mean and encompass the notions of “including,”“include,”“consist(ing) essentially of,” and “consist(ing) of. The use of “for example,”“e.g.,”“such as,” and“including” to list illustrative examples does not limit to only the listed examples. Thus,“for example” or“such as” means “for example, but not limited to” or“such as, but not limited to” and encompasses other similar or equivalent examples.

[00130] Generally, as used herein a hyphen

or dash

in a range of values is“to” or “through”; a“>” is“above” or“greater-than”; a“>” is“at least” or“greater-than or equal to”; a “<” is“below” or“less-than”; and a“£” is“at most” or“less-than or equal to.” On an individual basis, each of the aforementioned applications for patent, patents, and/or patent application publications, is expressly incorporated herein by reference in its entirety in one or more non limiting embodiments.

[00131] It is to be understood that the appended claims are not limited to express and particular compounds, compositions, or methods described in the detailed description, which may vary between particular embodiments which fall within the scope of the appended claims. With respect to any Markush groups relied upon herein for describing particular features or aspects of various embodiments, different, special, and/or unexpected results may be obtained from each member of the respective Markush group independent from all other Markush members. Each member of a Markush group may be relied upon individually and or in combination and provides adequate support for specific embodiments within the scope of the appended claims.

[00132] Further, any ranges and subranges relied upon in describing various embodiments of the present invention independently and collectively fall within the scope of the appended claims, and are understood to describe and contemplate all ranges including whole and/or fractional values therein, even if such values are not expressly written herein. One of skill in the art readily recognizes that the enumerated ranges and subranges sufficiently describe and enable various embodiments of the present invention, and such ranges and subranges may be further delineated into relevant halves, thirds, quarters, fifths, and so on. As just one example, a range“of from 0.1 to 0.9” may be further delineated into a lower third, i.e., from 0.1 to 0.3, a middle third, i.e., from 0.4 to 0.6, and an upper third, i.e., from 0.7 to 0.9, which individually and collectively are within the scope of the appended claims, and may be relied upon individually and/or collectively and provide adequate support for specific embodiments within the scope of the appended claims. In addition, with respect to the language which defines or modifies a range, such as“at least,”“greater than,”“less than,”“no more than,” and the like, it is to be understood that such language includes subranges and/or an upper or lower limit. As another example, a range of“at least 10” inherently includes a subrange of from at least 10 to 35, a subrange of from at least 10 to 25, a subrange of from 25 to 35, and so on, and each subrange may be relied upon individually and/or collectively and provides adequate support for specific embodiments within the scope of the appended claims. Finally, an individual number within a disclosed range may be relied upon and provides adequate support for specific embodiments within the scope of the appended claims. For example, a range“of from 1 to 9” includes various individual integers, such as 3, as well as individual numbers including a decimal point (or fraction), such as 4.1 , which may be relied upon and provide adequate support for specific embodiments within the scope of the appended claims.

[00133] The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. The invention may be practiced otherwise than as specifically described.

Claims

CLAIMS What is claimed is:

1 . A method for preparing a nanoparticle composition, the method comprising:

hydrogenating a hydrocarbon oil to give a hydrogenated hydrocarbon oil, wherein the hydrocarbon oil comprises a hydrocarbon having a carbon-carbon multiple bond;

forming a nanoparticle aerosol in a plasma reactor, wherein the nanoparticle aerosol comprises MH-functional nanoparticles entrained in a gas, where M is an independently selected Group IV element; and

collecting the MH-functional nanoparticles from the nanoparticle aerosol in a capture fluid comprising the hydrogenated hydrocarbon oil, thereby preparing the nanoparticle composition.

2. The method of claim 1 , wherein the MH-functional nanoparticles are immiscible in the hydrocarbon oil, wherein the MH-functional nanoparticles are immiscible in the hydrogenated hydrocarbon oil, and wherein the carbon-carbon multiple bond of the hydrocarbon of the hydrocarbon oil is reactive with the MH groups of the MH-functional nanoparticles to yield nanoparticles miscible with the hydrocarbon oil and with the hydrogenated hydrocarbon oil.

3. The method of claim 1 or claim 2, wherein the hydrocarbon oil comprises more unsaturated groups than the hydrogenated hydrocarbon oil, and wherein: (i) the hydrogenated hydrocarbon oil comprises unsaturated groups in an amount of less than 5 parts per million based on a total number of carbon-carbon bonds in the hydrogenated hydrocarbon oil; (ii) the capture fluid comprises unsaturated groups in an amount of less than 5 parts per million based on a total number of carbon-carbon bonds in the capture fluid prior to collecting the MH-functional nanoparticles therein; or (iii) both (i) and (ii).

4. The method of any one of claims 1 -3, wherein: (i) the capture fluid comprises unsaturated groups in an amount of less than 30% of the total number of MH functional groups of the MH-functional nanoparticles collected from the nanoparticle aerosol; (ii) the hydrogenated hydrocarbon oil comprises unsaturated groups in an amount of less than 30% of the total number of MH functional groups of the MH-functional nanoparticles collected from the nanoparticle aerosol; or (iii) both (i) and (ii).

5. The method of any one of claims 1 -4, wherein (i) the hydrogenated hydrocarbon oil comprises a viscosity of from 5 to 200 centipoise at 25 °C; (ii) the capture fluid comprises a viscosity of from 5 to 200 centipoise at 25‘C; or (iii) both (i) and (ii).

6. The method of any one of claims 1 -5, wherein hydrogenating the hydrocarbon oil comprises combining hydrogen gas and the hydrocarbon oil in the presence of a catalyst.

7. The method of any one of claims 1 -6, wherein: (i) prior to the hydrogenating, the amount of carbon-carbon multiple bonds in the hydrocarbon oil is reduced via previous hydrogenation and/or distillation; (ii) the hydrocarbon oil comprises a polymerized alkylene having residual unsaturation; or (iii) both (i) and (ii).

8. The method of any one of claims 1 -7, wherein forming the nanoparticle aerosol comprises:

applying a preselected radio frequency having a continuous frequency of from 10 to 500 MHz and a coupled power of from 5 to 1000 W to a reactant gas mixture in the plasma reactor, the plasma reactor having a reactant gas inlet and an outlet defining an aperture, to generate a plasma for a time sufficient to form the nanoparticle aerosol comprising MH- functional nanoparticles in a gas;

wherein the reactant gas mixture comprises a first precursor gas containing element M, and at least one inert gas.

9. The method of any one of claims 1 -8, further comprising:

introducing the nanoparticle aerosol into a diffusion pump from the plasma reactor; heating the capture fluid in a reservoir to form a vapor and sending the vapor through a jet assembly;

emitting the vapor through a nozzle into a chamber of the diffusion pump and condensing the vapor to form a condensate comprising the capture fluid;

flowing the condensate back to the reservoir; and

capturing the MX-functional nanoparticles of the nanoparticle aerosol in the condensate comprising the capture fluid.

10. The method of any one of claims 1 -9, wherein the MH-functional nanoparticles are collected in a capture fluid at a pressure of less than 1 x10 5 Torr.

1 1 . The method of any one of claims 1 -10, wherein the MH-functional nanoparticles further comprise MX-functionality, where M is an independently selected Group IV element and functional group X is a halogen atom independently selected from F, Cl, Br, and I.

12. The method of any one of claims 1 -1 1 , wherein the capture fluid further comprises a functionalization compound including a functional group Y reactive with the MH and/or MX groups of the MH-functional nanoparticles; and wherein the method further comprises reacting the functional group Y of the functionalization compound and the MH and/or MX groups of the MH-functional nanoparticles to give functionalized nanoparticles.

13. The method of claim 12, wherein the functional group Y of the functionalization compound comprises an aliphatic carbon-carbon multiple bond that is reacted with the MH groups of the MH-functional nanoparticles.

14. The method of claim 12, wherein: (i) the functional group Y of the functionalization compound Y comprises a nucleophilic functional group reactive with the MX groups of the MH-functional nanoparticles; (ii) the functionalization compound is selected from the group of an alcohol compound, a thiol compound, a cyanate compound, an amine compound, an azide compound, a nitrile compound, a carboxylic acid compound, a sulfide compound, an amide compound, a phosphine compound, a metal halide compound, a terminal alkyne compound, an organometallic compound, an alkali metal amide compound, a metal thiolate compound, and combinations thereof; or (iii) both (i) and (ii).

15. The method of any one of claims 1 1 -14, wherein the functionalization compound further comprises a functional group Z that is convertible to a hydrophilic functional group, and wherein: (i) the functional group Z comprises an ester group, an acid halide group, an amide group, an acetal group, a ketal group, a nitrile group, a silyl ether group, an epoxide group, a disulfide group, an ethylenically unsaturated group, an oxazoline group, an anhydride group, or a combination thereof; (ii) the method further comprises the step of converting the functional group Z to a hydrophilic functional group; or (iii) both (i) and (ii).

16. The method of claim 15, wherein the hydrophilic functional group comprises a carboxylic acid group, an alcohol group, a hydroxyl group, an azide group, a silyl ether group, an ether group, a phosphonate group, a sulfonate group, a thiol group, an amine group, an anhydride group, an acetal group, a ketal group, or a combination thereof.

17. The method of any one of claims 12-16, wherein a concentration of the functionalization compound is from 0.01 wt% to 10 wt% measured with respect to the capture fluid.

18. The method of any one of claims 1 -17, further comprising separating the nanoparticles and the capture fluid to obtain separated nanoparticles.

19. The method of claim 17, wherein: (i) the separated nanoparticles are a solid; (ii) the method further comprises suspending the separated nanoparticles in a polar solvent comprising water and/or a dipolar aprotic organic solvent; or (iii) both (i) and (ii).

20. A nanoparticle composition prepared in accordance with the method of any one of claims 1 -19.