CN102897722A

CN102897722A - Alpha-In2Se3 nano-grade flower-ball solvothermal synthesizing method

Info

Publication number: CN102897722A
Application number: CN201210312074XA
Authority: CN
Inventors: 施伟东; 刘裴; 范伟强; 于帅
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2012-08-29
Filing date: 2012-08-29
Publication date: 2013-01-30
Anticipated expiration: 2032-08-29
Also published as: CN102897722B

Abstract

The invention belongs to the technical field of environment-friendly nano-grade materials, and relates to a preparation method of a nano-grade material. The invention especially relates to an alpha-In2Se3 nano-grade flower-ball solvothermal synthesizing method. According to the method provided by the invention, oleic acid is adopted as a solvent, ascorbic acid is adopted as a reducing agent, and indium nitrate and selenium powder are subjected to a solvothermal synthesizing reaction in a reaction kettle; and the obtained material is washed by using anhydrous ethanol, and is subjected to centrifugal separation drying, such that the nano-grade flower-balls are obtained. Inferred from the growth mechanism, the method can be used in preparations of other selenium metal compound nano-grade materials. The preparation method provided by the invention is simple and green, and has the advantages of low cost, high controllability, and good product crystallinity. According to analyses by using low-magnification scanning electron micrograph (SEM), high-magnification scanning electron micrograph (SEM), and transmission electron micrograph (TEM), the alpha-In2Se3prepared nano-grade flower-balls have diameters of 1-2 micrometers, and are composed of nano-sheets with thicknesses of 13-15nm.

Description

A kind of α-In 2Se 3Nanometer bouquet solvent process for thermosynthesizing

Technical field

The invention belongs to environmentally friendly technical field of nano material, relate to the preparations of nanomaterials method, especially relate to a kind of α-In ₂Se ₃Nanometer bouquet solvent process for thermosynthesizing.

Background technology

Selenide metal semiconductor nano material is because its unique physicals and chemical property, can be widely used in energy, medicine, the important field of sensor simultaneously and caused more and more people's attention.In numerous selenide, indium selenide is as important III-VI main group compound, the laminate structure that is formed by the Se-In-In-Se key, strong covalent linkage and faint Van der Waals force are used thereby indium selenide has been had widely at devices such as phase converter, polarized radiation, photovoltaic solar cells, lithium cell, fluorescent apparatus, dielectric medium, field-effect transistors so that it has the performances such as anisotropy, electricity, optics and magnetics, catalysis and air-sensitive of height between layers.Simultaneously, indium selenide can also prepare different three urmaterie such as CuInSe as structural unit ₂, AgInSe ₂With quaternary substance C u (In, Ga) Se ₂, be widely used on the photoelectric material device and these materials also are good photoelectric materials.In addition, indium selenide is the photoelectric material that a kind of direct band gap is 1.7eV, because photoelectronic anisotropy has very high uptake factor in visible light wave scope, can effectively convert solar energy into electrical energy, and be a kind of photovoltaic energy material of excellence.Simultaneously, compare with the photoelectric material that cadmium selenide and lead selenide etc. are good, indium selenide also has hypotoxicity and environment friendly in the low band-gap nano material.

Although the research for indium selenide never rested, synthesize indium selenide not a duck soup single, pure phase.In building-up process, the difficulty that indium selenide runs into mainly comes from the limitation of indium selenide phasor.Indium selenide has InSe, In ₂Se ₃, In ₄Se ₃And In ₆Se ₇The array configuration of four kinds of complexity, these several different moietys often are present in the indium selenide within a certain scope simultaneously.Other In only ₂Se ₃This composition form, it becomes phase system just complicated especially, for example, In ₂Se ₃α is arranged, beta, gamma, five kinds of crystal formations of δ and κ, and be easy between crystal formation and the crystal formation mutually change, so will expect the In of single composition and single crystal form ₂Se ₃, especially difficulty seems.

So far, relevant synthetic In ₂Se ₃Method report out successively, but most synthetic method then is confined to traditional methods such as gas-phase synthesizing method, organic chemistry steam decomposition method and electrochemical deposition method.And the instrument of the high-end precision of above-mentioned synthetic method needs, temperature of reaction is at 400 ~ 1000 ℃, and energy consumption is large, and can produce poisonous gas, and human body and environment are caused certain harm, and the sample that these methods obtain also has the characteristics such as heterogeneity and low yield.Therefore seek simple, cheap, green, a controlled method, synthetic InSe nanometer structure is necessary and challenging.

Hydrothermal method has the advantages such as equipment is simple, raw material obtains easily, obtain product purity height, good uniformity, chemical constitution precise control and is subject to many researchers' favor.Hydrothermal method is in special closed reactor (autoclave), take fluids such as water or organic solvents as reactive material, by reaction system being heated to critical temperature (or near critical temperature), create a high-temperature high-voltage reaction environment, impel reaction in liquid phase or gas phase, to carry out, make originally indissoluble or insoluble material solvent and recrystallization, process separation and thermal treatment obtain a kind of effective ways of product again.Hydrothermal method has the following advantages: temperature (generally between 120 ~ 220 ℃) liquid phase control during adopt (1), and energy consumption is relatively low, and suitability is wide, both can be used for the less nanoparticle preparation of size, also can obtain larger-size monocrystalline; (2) raw material is relatively inexpensive is easy to get, and reaction is carried out in the quick convection current of liquid phase, and productive rate is high, phase is even, purity is high, the well-crystallized, and shape size is controlled; (3) in water-heat process, can pass through conditioned reaction temperature, pressure, time, pH value, precursor and tensio-active agent etc., reach the purpose of effective control reaction and growth characteristics; (4) reaction is carried out in the container of sealing, is applicable to the building-up reactions in the poisonous system, but environmental contamination reduction.

But rarely have report but utilize hydrothermal method to prepare indium selenide, only have 2011, the human ethanol such as poplar have gone out γ-In as solvent at 220 ℃ of lower Hydrothermal Synthesiss ₂Se ₃Microballoon, the diameter of this ball is at the 2-4 micron.Because the size of material has a great impact for character, so synthetic undersized indium selenide is necessary.In addition, up to now, also not for the controlled α-In of pattern ₂Se ₃The report that solvent thermal is synthetic.Therefore, solvent-applied process for thermosynthesizing, synthetic single component, the controlled α-In of pattern ₂Se ₃Imperative.

Summary of the invention

For the defective that exists in the prior art and deficiency, the invention provides a kind of α-In ₂Se ₃The solvent process for thermosynthesizing of nanometer bouquet is take oleic acid as solvent, and xitix is reductive agent, with indium nitrate, selenium powder solvent thermal building-up reactions in reactor, then uses absolute ethanol washing, and makes after the centrifugation drying.Infer that from growth mechanism the method can be applicable to other selenium metallic compound nano material preparations.

A kind of α-In ₂Se ₃Nanometer bouquet solvent process for thermosynthesizing, described solvent thermal building-up reactions comprises the steps:

Steps A, take by weighing a certain amount of indium nitrate, selenium powder, xitix and mix in reactor, wherein, the mol ratio of described indium nitrate, selenium powder, xitix is 3:1:1 ~ 2;

Step B, adding oleic acid stir 30min, and the volume of wherein said oleic acid accounts for 60% ~ 80% of reactor;

Step C, with reactor in 190 ℃ ~ 220 ℃ lower reaction 12h ~ 24h, then be cooled to room temperature.

In a preferred embodiment of the present invention, the mol ratio of described indium nitrate, selenium powder, xitix is 3:1:1;

The volume of described oleic acid accounts for 80% of reactor;

Described reactor is in 200 ℃ of lower reaction 24h.

Resulting product is used absolute ethanol washing at ambient temperature, and centrifugation gets its lower sediment, obtain the powder of black after the vacuum-drying.

α-the In that is prepared from according to above-mentioned solvent process for thermosynthesizing ₂Se ₃The nanometer bouquet is from the analysis to its low power scanning electron microscope (SEM) photograph (SEM), high power scanning electron microscope (SEM) photograph (SEM) and transmission electron microscope picture (TEM), described α-In ₂Se ₃The nano flower spherical diameter is at 1 ~ 2 micron, is that the nanometer sheet of 13 ~ 15nm forms by thickness.

Beneficial effect

Preparation method of the present invention is simple, with low cost, controllability is strong, product good crystallinity, environmental protection.

Description of drawings

The X-ray diffraction analysis figure (XRD) of the flower ball-shaped indium selenide of Fig. 1 preparation;

The low power scanning electron microscope (SEM) photograph (SEM) of the flower ball-shaped indium selenide of Fig. 2 preparation;

The high power scanning electron microscope (SEM) photograph (SEM) of the flower ball-shaped indium selenide of Fig. 3 preparation;

The flower ball-shaped indium selenide transmission electron microscope picture (TEM) of Fig. 4 preparation.

Embodiment

The present invention is described in detail below in conjunction with embodiment, so that those skilled in the art understand the present invention better, but the present invention is not limited to following examples.

Embodiment 1:

A kind of synthetic α-In ₂Se ₃The solvent-thermal method of nanometer bouquet, concrete steps are as follows:

(1) take by weighing respectively the 0.2292g indium nitrate with electronic balance, 0.0158g selenium powder, 0.0352g xitix, 30ml oleic acid are in the 50ml reactor, and magneton stirred 30 minutes;

(2) the reactor sealing was put into 200 ℃ of baking oven constant temperature 24 hours, then naturally cool to room temperature, use absolute ethanol washing 8 times, drying obtains black flower ball-shaped indium selenide in 60 ℃ of vacuum drying ovens.

Fig. 1 is the XRD figure of the flower ball-shaped indium selenide of preparation, as can be seen from the figure the peak type of resulting material and the card 34-1313 of JCPDS (JCPDS) match, and do not have the peak of other impurity in this peak, illustrate that obtain is the α-In of pure phase ₂Se ₃

Fig. 2 is the low power SEM figure of the flower ball-shaped indium selenide of preparation, and as can be seen from the figure, the bouquet dispersiveness is relatively good, and surface ratio is more coarse, and diameter is greatly about the 1-2 micron.

Fig. 3 is the high power SEM figure of the flower ball-shaped indium selenide of preparation, and as can be seen from the figure, bouquet is that nanometer sheet about 15 nanometers forms by thickness.

Fig. 4 is the flower ball-shaped indium selenide TEM figure of preparation, understands furtherly what bouquet was comprised of sheet.

Embodiment 2:

(1) take by weighing respectively the 0.2292g indium nitrate with electronic balance, 0.0158g selenium powder, 0.0704g xitix, 30ml oleic acid are in the 50ml reactor, and magneton stirred 30 minutes;

Embodiment 3:

(1) take by weighing respectively the 0.2292g indium nitrate with electronic balance, 0.0158g selenium powder, 0.0352g xitix, 40ml oleic acid are in the 50ml reactor, and magneton stirred 30 minutes;

Embodiment 4:

(2) the reactor sealing was put into 190 ℃ of baking oven constant temperature 24 hours, then naturally cool to room temperature, use absolute ethanol washing 8 times, drying obtains black flower ball-shaped indium selenide in 60 ℃ of vacuum drying ovens.

Embodiment 5:

(2) the reactor sealing was put into 220 ℃ of baking oven constant temperature 24 hours, then naturally cool to room temperature, use absolute ethanol washing 8 times, drying obtains black flower ball-shaped indium selenide in 60 ℃ of vacuum drying ovens.

Embodiment 6:

(2) the reactor sealing was put into 200 ℃ of baking oven constant temperature 12 hours, then naturally cool to room temperature, use absolute ethanol washing 8 times, drying obtains black flower ball-shaped indium selenide in 60 ℃ of vacuum drying ovens.

Claims

1. α-In ₂Se ₃Nanometer bouquet solvent process for thermosynthesizing is take oleic acid as solvent, and xitix is reductive agent, with indium nitrate, selenium powder solvent thermal building-up reactions in reactor, then uses absolute ethanol washing, and makes after the centrifugation drying.

2. α-In according to claim 1 ₂Se ₃Nanometer bouquet solvent process for thermosynthesizing is characterized in that, described solvent thermal building-up reactions comprises the steps:

3. α-In according to claim 2 ₂Se ₃Nanometer bouquet solvent process for thermosynthesizing is characterized in that, the mol ratio of described indium nitrate, selenium powder, xitix is 3:1:1;

The volume of described oleic acid accounts for 80% of reactor;

Described reactor is in 200 ℃ of lower reaction 24h.

4. α-In of being prepared from of method according to claim 1 ₂Se ₃The nanometer bouquet.

5. α-In according to claim 4 ₂Se ₃The nanometer bouquet is characterized in that described bouquet diameter is at 1 ~ 2 micron.

6. α-In according to claim 4 ₂Se ₃The nanometer bouquet is characterized in that described bouquet is comprised of the nanometer sheet of thickness by 13 ~ 15nm.