CN107686729B - Preparation method of metal tungsten quantum dots - Google Patents
Preparation method of metal tungsten quantum dots Download PDFInfo
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- CN107686729B CN107686729B CN201710914387.5A CN201710914387A CN107686729B CN 107686729 B CN107686729 B CN 107686729B CN 201710914387 A CN201710914387 A CN 201710914387A CN 107686729 B CN107686729 B CN 107686729B
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- 229910052751 metal Inorganic materials 0.000 title claims abstract description 71
- 239000002184 metal Substances 0.000 title claims abstract description 71
- 150000003657 tungsten Chemical class 0.000 title claims abstract description 60
- 238000002360 preparation method Methods 0.000 title claims abstract description 28
- 239000002086 nanomaterial Substances 0.000 claims abstract description 33
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910001930 tungsten oxide Inorganic materials 0.000 claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 28
- 238000000137 annealing Methods 0.000 claims abstract description 25
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- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 15
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- 230000002950 deficient Effects 0.000 claims abstract description 6
- 239000002070 nanowire Substances 0.000 claims description 62
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 42
- 229910052721 tungsten Inorganic materials 0.000 claims description 42
- 239000010937 tungsten Substances 0.000 claims description 42
- 238000002207 thermal evaporation Methods 0.000 claims description 23
- 239000002096 quantum dot Substances 0.000 claims description 20
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- B22—CASTING; POWDER METALLURGY
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- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
- B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
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- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
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- C09K11/67—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing refractory metals
- C09K11/68—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing refractory metals containing chromium, molybdenum or tungsten
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- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/0021—Reactive sputtering or evaporation
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- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/24—Vacuum evaporation
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- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
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Abstract
The invention relates to a preparation method of metal tungsten quantum dots, which comprises the following steps: placing the tungsten oxide nano structure in an oxygen-deficient environment or a reducing atmosphere protected by inert gas for high-temperature annealing treatment, growing metal tungsten quantum dots on the surface of the tungsten oxide nano structure by adjusting the time of the high-temperature annealing treatment, and then separating the tungsten oxide nano structure and the metal tungsten quantum dots to obtain the metal tungsten quantum dots. The preparation method has the advantages of simple process steps, single raw material, easy realization of preparation conditions, controllable particle size of the prepared metal tungsten quantum dots and the like.
Description
Technical Field
The invention belongs to the technical field of preparation of nano powder of high-temperature metal materials, and particularly relates to a preparation method of metal tungsten quantum dots.
Background
The nano powder material has small particle size and large specific surface area, and shows 'size effect', 'surface and interface effect' and 'quantum size effect' different from those of a bulk material, so that the nano powder material can be widely applied to the fields of surfactants, single-electron devices, lithium battery electrode materials, electron field emission materials, sensors and the like. Generally, the smaller the particle size of the nano powder, the more significant the quantum size effect and the more excellent the performance, but the smaller the particle size of the nano powder, the more easily reagglomerated the nano powder during the preparation process, so that the particle size of the nano powder becomes larger. Therefore, the preparation of a nano powder material having good dispersibility and a small particle size has become an important research direction in this field.
The metal tungsten has excellent performances of extremely high melting point (3410 ℃), high density, high strength, low thermal expansion coefficient, good corrosion resistance, good thermionic emission capability and the like, and is widely applied to various fields such as aerospace, military industry, electronic industry and the like, from the 20 th century in the 60 th year, students begin to carry out deep research on the preparation of tungsten and compound nano-powder thereof, tungsten particles develop from the initial micron-scale to the present nanometer-scale, and even the students prepare ultrafine β -W nano-particles in liquid nitrogen by a laser ablation technology, the average particle size of the ultrafine β -W nano-particles is as small as 3nm3、NaBH4Etc.) by chemically reacting a tungsten salt (W (CO)6、WCl6Etc.) to obtain the nano-scale tungsten particles, but the method has the defects of complicated process steps, a plurality of used reagents, use of strong acid and strong base, environmental friendliness and the like.
Therefore, it is very important to develop a method for preparing metal tungsten nano-powder, which has simple process, low preparation cost and environmental friendliness.
Disclosure of Invention
Based on the above, the invention aims to provide a preparation method of the metal tungsten quantum dots, which has the advantages of simple process steps, single raw material, easy realization of preparation conditions, controllable particle size of the prepared metal tungsten quantum dots and the like.
The technical scheme adopted by the invention is as follows:
a preparation method of metal tungsten quantum dots comprises the following steps: placing the tungsten oxide nano structure in an oxygen-deficient environment or a reducing atmosphere protected by inert gas for high-temperature annealing treatment, growing metal tungsten quantum dots on the surface of the tungsten oxide nano structure by adjusting the time of the high-temperature annealing treatment, and then separating the tungsten oxide nano structure and the metal tungsten quantum dots to obtain the metal tungsten quantum dots.
The preparation method takes the tungsten oxide nano structure as a raw material, and leads the surface of the tungsten oxide nano structure to generate decomposition reaction or reduction reaction through high-temperature annealing treatment, thereby separating out metal tungsten particles. Secondly, the degree of decomposition reaction or reduction reaction can be controlled by adjusting the time of high-temperature annealing treatment, so that the particle size of the metal tungsten particles can be effectively regulated and controlled. Moreover, the size of the tungsten oxide nano structure is small enough and the specific surface area is large, so that the particle size of the metal tungsten particles can reach the quantum dot level. Moreover, since the metallic tungsten quantum dots are formed by growing on the surface of the tungsten oxide nanostructure, aggregation is not likely to occur, resulting in an increase in particle size, and the size thereof can be maintained stable.
Compared with the existing laser ablation technology, thermal plasma technology and tungsten salt pyrolysis method, the method has the advantages of simple process steps, single raw material, no need of using various reagents, environmental friendliness, easy realization and control of preparation conditions and low preparation cost.
Further, the temperature of the high-temperature annealing treatment is 1200 ℃ or more, and the time is 10-30 minutes.
The high-temperature annealing treatment needs to reach a proper temperature to promote the decomposition reaction or the reduction reaction of the surface of the tungsten oxide nano structure. If the time of the high-temperature annealing treatment is too short, the metallic tungsten quantum dots cannot be sufficiently precipitated, and if the time is too long, the particle size of the precipitated metallic tungsten particles is too large to exceed the quantum dot level, so that the time of the high-temperature annealing treatment needs to be controlled within an appropriate range.
Further, the tungsten oxide nano structure is prepared by a vacuum thermal evaporation method.
Further, the tungsten oxide nano-structure is obtained by heating and evaporating a tungsten source in an oxygen-containing atmosphere and then depositing on a substrate, wherein the tungsten source is bulk tungsten.
The preparation method adopts a vacuum thermal evaporation method to prepare the tungsten oxide nano structure, has simple process steps, single raw material, low preparation cost and easily controlled preparation conditions, and the obtained tungsten oxide nano structure has controllable appearance, high crystallinity and stable structure.
Further, the tungsten oxide nano structure is W18O49A nanowire.
Furthermore, the size of the tungsten oxide nano structure is 50-500nm, and the particle size of the prepared metal tungsten quantum dot is 1-20 nm. By limiting the size of the tungsten oxide nano structure within a proper range, the metal tungsten particles formed on the surface of the tungsten oxide nano structure are ensured to reach the quantum dot level.
Further, the step of separating the tungsten oxide nano structure from the metal tungsten quantum dot is as follows: putting the tungsten oxide nano structure with the metal tungsten quantum dots growing on the surface into a solvent, separating the metal tungsten quantum dots from the tungsten oxide nano structure by adopting an ultrasonic oscillation method, filtering to remove the tungsten oxide nano structure to obtain a solution containing the metal tungsten quantum dots, and drying to remove the solvent in the solution containing the metal tungsten quantum dots to obtain the metal tungsten quantum dot powder.
Further, the preparation method specifically comprises the following steps:
(1)W18O49preparing the nano wire: connecting a tungsten source into an evaporation electrode of a vacuum thermal evaporation coating machine, placing a substrate at a position 2-100 mm away from the tungsten source, vacuumizing a vacuum coating cavity, introducing oxygen and inert gas with a flow ratio of 1:100, turning on a thermal evaporation power supply, heating the tungsten source to 1400 ℃ from room temperature, preserving heat for 20 minutes, turning off the thermal evaporation power supply, cooling the substrate to room temperature, and obtaining W grown on the substrate18O49A nanowire;
(2) preparing the metal tungsten quantum dots: interrupting oxygen supply, vacuumizing the vacuum coating cavity, introducing inert gas, turning on a thermal evaporation power supply, heating the substrate from room temperature to 1600 ℃, performing high-temperature annealing treatment at 1600 ℃ for 20 minutes, then turning off the thermal evaporation power supply,cooling the substrate to room temperature to obtain the growth on W18O49Metal tungsten quantum dots on the surface of the nanowire;
(3)W18O49separation of nanowires from metallic tungsten quantum dots: growing W with metal tungsten quantum dots on the surface18O49Putting the nanowires into deionized water, performing ultrasonic oscillation by using an ultrasonic cleaner, and screening W by using a screen18O49Filtering and removing the nanowires to obtain deionized water containing metal tungsten quantum dots;
(4) extracting the metal tungsten quantum dots: and (3) putting deionized water containing the metal tungsten quantum dots into a drying oven at 90 ℃ for drying, and obtaining metal tungsten quantum dot powder after the deionized water is completely volatilized.
Vacuum thermal evaporation coating machine is used for completing vacuum thermal evaporation preparation of W18O49The preparation method has the advantages that the steps of preparing the metal tungsten quantum dots through the nanowires and the high-temperature annealing treatment are not needed, other equipment is not needed in the middle, the preparation efficiency is high, the preparation conditions are easy to adjust, the operation controllability is improved, the preparation cost is reduced, the time of the high-temperature annealing treatment is convenient to adjust, and the particle size of the metal tungsten quantum dots is adjusted and controlled.
Further, in step (2), the substrate is heated from room temperature to 1600 ℃ at a temperature rising rate of 80 ℃/min, and the substrate is cooled to room temperature at a temperature lowering rate of 100 ℃/min. By limiting the heating and cooling rates, the method is favorable for maintaining W before high-temperature annealing treatment18O49The structure of the nanowire is stable, and the structure of the metal tungsten quantum dot after high-temperature annealing treatment is maintained to be stable.
The invention also provides the metal tungsten quantum dot prepared by any one of the preparation methods.
For a better understanding and practice, the invention is described in detail below with reference to the accompanying drawings.
Drawings
FIG. 1 shows W obtained in step (1)18O49TEM image of the nanowires; wherein, FIG. 1(a) is a single W18O49A low power TEM image of the nanowire, FIG. 1(b) is an enlarged TEM image of the box area in FIG. 1(a), and FIG. 1(c) is FIG. 1(b)) HRTEM of the middle box area.
FIG. 2 shows W obtained in step (1)18O49XRD pattern of the nanowires.
FIG. 3 shows W obtained in step (2)18O49TEM image of the nanowires; wherein, in FIG. 3(a), W is18O49A low power TEM image of the nanowires, fig. 3(b) is a partially enlarged TEM image of fig. 3(a), and fig. 3(c) is an HRTEM image of the box area of fig. 3 (b).
FIG. 4 shows W obtained in step (2)18O49XRD pattern of the nanowires.
FIG. 5 shows W before and after the ultrasonic oscillation in step (3)18O49TEM image of the nanowires; wherein, FIG. 5(a) is W before ultrasonic oscillation18O49TEM image of nanowire, FIG. 5(b) is W after ultrasonic oscillation18O49TEM images of nanowires.
Detailed Description
This example uses W18O49The method for preparing the metal tungsten quantum dots by high-temperature annealing treatment in an oxygen-deficient environment protected by inert gas by using the nanowires as raw materials comprises the following steps:
(1)W18O49preparing the nano wire: connecting a tungsten boat to an evaporation electrode of a vacuum thermal evaporation coating machine, placing carbon fiber cloth at a position 2 mm away from the tungsten boat, vacuumizing the vacuum coating cavity to 6.5Pa, introducing oxygen and argon with a flow ratio of 1:100, turning on a thermal evaporation power supply, heating the tungsten boat from room temperature to 1400 ℃ at a heating rate of 80 ℃/min, preserving heat for 20 min, turning off the thermal evaporation power supply, cooling the carbon fiber cloth to room temperature at a cooling rate of 100 ℃/min to obtain W growing on the carbon fiber cloth18O49A nanowire.
(2) Preparing the metal tungsten quantum dots: closing the oxygen valve, interrupting the oxygen supply, vacuumizing the vacuum coating cavity to 6.5Pa, introducing argon, turning on a thermal evaporation power supply, and heating to coat W at a temperature rise rate of 80 ℃/min18O49Heating the carbon fiber cloth of the nano wire from room temperature to 1600 ℃, carrying out high-temperature annealing treatment at 1600 ℃ for 20 minutes, and then closing thermal evaporationA power supply, the carbon fiber cloth is cooled to room temperature at a cooling rate of 100 ℃/min, W18O49Decomposition reaction occurs on the surface of the nanowire, and thus growth on W is obtained18O49And the metal tungsten quantum dots on the surface of the nanowire.
(3)W18O49Separation of nanowires from metallic tungsten quantum dots: growing W with metal tungsten quantum dots on the surface18O49Putting the nanowires into deionized water, then carrying out ultrasonic oscillation by using an ultrasonic cleaning machine, wherein the oscillation power is 240W, the frequency is 40kHz, the oscillation time is 5-20 minutes, and then blocking W18O49A screen mesh of nanowires but allowing metallic tungsten quantum dots to pass through18O49And filtering and removing the nanowires to obtain the deionized water containing the metal tungsten quantum dots.
(4) Extracting the metal tungsten quantum dots: and (3) putting deionized water containing the metal tungsten quantum dots into a drying oven at 90 ℃ for drying, and obtaining metal tungsten quantum dot powder after the deionized water is completely volatilized.
For the W grown on the carbon fiber cloth obtained in the step (1) of the present example18O49Nanowire and W with metal tungsten quantum dots growing on surface obtained in step (2)18O49And respectively carrying out TEM and XRD tests on the nanowire to characterize the surface appearance and the phase structure of the nanowire.
Please refer to fig. 1, which shows W obtained in step (1)18O49TEM image of the nanowires; wherein, FIG. 1(a) is a single W18O49A low power TEM image of the nanowire, fig. 1(b) is an enlarged TEM image of the box area in fig. 1(a), and fig. 1(c) is an HRTEM image of the box area in fig. 1 (b).
As can be seen from the figure, W obtained in step (1)18O49The surface of the nanowire is smooth, and the diameter of the nanowire is about 360 nm. HRTEM analysis shows that the nano wire has a surface spacing of 0.372nm and is in accordance with the W of cubic system18O49The interplanar spacing of the (010) crystal plane of (c).
Please refer to fig. 2, which shows W obtained in step (1)18O49XRD pattern of the nanowires.
As can be seen from the figure, it is,(010) the diffraction peak position of the crystal orientation corresponds to the W of monoclinic system18O49(JCPDS card: No. PDF-36-0101) having no diffraction peak other than the broad peak and stray peak at 20-30 degrees, indicating that pure W is obtained by the vacuum thermal evaporation method of step (1)18O49Nanowires, without the presence of metallic tungsten.
Please refer to fig. 3, which shows W obtained in step (2)18O49TEM image of the nanowires; wherein, in FIG. 3(a), W is18O49A low power TEM image of the nanowires, fig. 3(b) is a partially enlarged TEM image of fig. 3(a), and fig. 3(c) is an HRTEM image of the box area of fig. 3 (b).
As can be seen from the figure, W obtained in step (2)18O49The surface of the nano wire is rough, and quantum dots with the particle size of about 10nm are grown on the surface of the nano wire. According to HRTEM analysis, the surface spacing of the quantum dots is 0.224nm, and the surface spacing of the (110) crystal face of the metal tungsten in the cubic system is met.
Please refer to fig. 4, which shows W obtained in step (2)18O49XRD pattern of the nanowires.
As can be seen from the figure, the diffraction peak position of the (010) crystal direction corresponds to the W of the monoclinic system18O49(JCPDS card: No. PDF-36-0101), in addition to the above, it is clear that the diffraction peak positions of the crystal orientations of (110), (200) and (211) correspond to the cubic metallic tungsten (JCPDS card: No. PDF-04-0806), which shows that W after high-temperature annealing treatment in an oxygen-deficient atmosphere protected by inert gas18O49Nanowires, the surface of which is presented with metallic tungsten.
FIG. 5 shows W before and after the ultrasonic oscillation in step (3)18O49TEM image of the nanowires; wherein, FIG. 5(a) is W before ultrasonic oscillation18O49TEM image of nanowire, FIG. 5(b) is W after ultrasonic oscillation18O49TEM images of nanowires.
As can be seen by comparing FIG. 5(a) with FIG. 5(b), W was observed before the ultrasonic oscillation18O49Granular quantum dots are attached to the surface of the nanowire, but after ultrasonic oscillation, W18O49The granular quantum dots on the surface of the nanowire disappear.The results show that ultrasonic oscillation can effectively convert W18O49And separating the nanowires from the metal tungsten quantum dots.
For example, in addition to the method for preparing the metal tungsten quantum dots by the high-temperature annealing treatment in the oxygen-deficient environment protected by the inert gas described in the above example, the high-temperature annealing treatment may be performed in a reducing atmosphere, and then the step (2) may be changed to: opening the vacuum coating cavity at W18O49Uniformly scattering carbon powder around the nanowire, closing a vacuum coating cavity, vacuumizing the cavity to 6.5Pa, then opening a thermal evaporation power supply, heating the carbon fiber cloth from room temperature to 1400 ℃ at a heating rate of 80 ℃/min, carrying out high-temperature annealing treatment at 1400 ℃ for 10 min, then closing the thermal evaporation power supply, cooling the carbon fiber cloth to room temperature at a cooling rate of 100 ℃/min, and W18O49The surface of the nanowire is subjected to reduction reaction, and then the nanowire is grown on W18O49Metal tungsten quantum dots on the surface of the nanowire; the operation of placing the carbon powder can be changed into the operation of introducing carbon monoxide or hydrogen; further, W18O49The nanowires can be prepared by a chemical solution method, etc., in addition to the vacuum thermal evaporation method.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.
Claims (4)
1. A preparation method of metal tungsten quantum dots is characterized by comprising the following steps: the method comprises the following steps: placing the tungsten oxide nano structure in an oxygen-deficient environment protected by inert gas for high-temperature annealing treatment, growing metal tungsten quantum dots on the surface of the tungsten oxide nano structure by adjusting the time of the high-temperature annealing treatment, and then separating the tungsten oxide nano structure and the metal tungsten quantum dots to obtain the metal tungsten quantum dots; the high-temperature annealing treatment temperature is 1200 ℃ or above, and the time is 10-30 minutes;
the tungsten oxide nano structure is prepared by a vacuum thermal evaporation method, and is obtained by heating and evaporating a tungsten source in an oxygen-containing atmosphere and then depositing on a substrate, wherein the tungsten source is bulk tungsten; the tungsten oxide nano structure is W18O49A nanowire;
the size of the tungsten oxide nano structure is 50-500nm, and the particle size of the prepared metal tungsten quantum dot is 1-20 nm.
2. The method for preparing the metal tungsten quantum dot according to claim 1, wherein the method comprises the following steps: the step of separating the tungsten oxide nano structure and the metal tungsten quantum dot comprises the following steps: putting the tungsten oxide nano structure with the metal tungsten quantum dots growing on the surface into a solvent, separating the metal tungsten quantum dots from the tungsten oxide nano structure by adopting an ultrasonic oscillation method, filtering to remove the tungsten oxide nano structure to obtain a solution containing the metal tungsten quantum dots, and drying to remove the solvent in the solution containing the metal tungsten quantum dots to obtain the metal tungsten quantum dot powder.
3. The method for preparing metallic tungsten quantum dots according to any one of claims 1 or 2, wherein: the method specifically comprises the following steps:
（1）W18O49preparing the nano wire: connecting a tungsten source into an evaporation electrode of a vacuum thermal evaporation coating machine, placing a substrate at a position 2-100 mm away from the tungsten source, vacuumizing a vacuum coating cavity, introducing oxygen and inert gas with a flow ratio of 1:100, turning on a thermal evaporation power supply, heating the tungsten source to 1400 ℃ from room temperature, preserving heat for 20 minutes, turning off the thermal evaporation power supply, cooling the substrate to room temperature, and obtaining W grown on the substrate18O49A nanowire;
(2) preparing the metal tungsten quantum dots: interrupting oxygen supply, vacuumizing the vacuum coating cavity, introducing inert gas, turning on a thermal evaporation power supply, heating the substrate from room temperature to 1600 ℃, performing high-temperature annealing treatment at 1600 ℃ for 20 minutes,then the thermal evaporation power is turned off, the substrate is cooled to room temperature, and the growth on W is obtained18O49Metal tungsten quantum dots on the surface of the nanowire;
（3）W18O49separation of nanowires from metallic tungsten quantum dots: growing W with metal tungsten quantum dots on the surface18O49Putting the nanowires into deionized water, performing ultrasonic oscillation by using an ultrasonic cleaner, and screening W by using a screen18O49Filtering and removing the nanowires to obtain deionized water containing metal tungsten quantum dots;
(4) extracting the metal tungsten quantum dots: and (3) putting deionized water containing the metal tungsten quantum dots into a drying oven at 90 ℃ for drying, and obtaining metal tungsten quantum dot powder after the deionized water is completely volatilized.
4. The method for preparing the metal tungsten quantum dot according to claim 3, wherein the method comprises the following steps: in step (2), the substrate is heated from room temperature to 1600 ℃ at a ramp rate of 80 ℃/min, and cooled to room temperature at a ramp rate of 100 ℃/min.
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| CN106623962A (en) * | 2016-12-31 | 2017-05-10 | 湖南省华京粉体材料有限公司 | Method for preparing nanometer tungsten powder by organizing sodium tungstate |
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Denomination of invention: A preparation method of tungsten metal quantum dots Granted publication date: 20200929 Pledgee: China Co. truction Bank Corp Yiyang branch Pledgor: HUNAN JINDIAO ENERGY TECHNOLOGY Co.,Ltd. Registration number: Y2024980009894 |