CN102897722B - Alpha-In2Se3 nano-grade flower-ball solvothermal synthesizing method - Google Patents

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 preparation method of nano material, especially relate to a kind of α-In ₂se ₃nanometer bouquet solvent process for thermosynthesizing.

Background technology

Selenide metal semiconductor nano material is due to 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 being formed by Se-In-In-Se key, strong covalent linkage and faint Van der Waals force make the performances such as its anisotropy, electricity, optics and magnetics, catalysis and air-sensitive with height between layers, thereby make indium selenide on the devices such as phase converter, polarized radiation, photovoltaic solar cells, lithium cell, fluorescent apparatus, dielectric medium, field-effect transistor, have application widely.Meanwhile, indium selenide can also be prepared three different urmaterie as CuInSe as structural unit ₂, AgInSe ₂with quaternary substance C u (In, Ga) Se ₂, be widely used on photoelectric material device and these materials are also good photoelectric materials.In addition, indium selenide is the photoelectric material that a kind of direct band gap is 1.7eV, due to photoelectronic anisotropy, within the scope of visible light wave, has very high uptake factor, can effectively convert solar energy into electrical energy, and be a kind of photovoltaic energy material of excellence., compare with the photoelectric material that cadmium selenide is good with lead selenide etc., indium selenide also has hypotoxicity and environment friendly in low band-gap nano material meanwhile.

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 ₇four kinds of complicated array configurations, these several different moietys are often present in indium selenide within a certain scope simultaneously.Only In in addition ₂se ₃this composition form, it becomes phase system just complicated especially, for example, In ₂se ₃there is α, beta, gamma, five kinds of crystal formations of δ and κ, and between crystal formation and crystal formation, be easy to 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 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 to certain harm, and the sample that these methods obtain also has the feature such as heterogeneity and low yield.Therefore find simple, cheap, green, a controlled method, synthetic InSe nanometer structure is necessary and challenging.

Hydrothermal method has the advantages such as the product purity that equipment is simple, raw material easily obtains, obtain is high, good uniformity, chemical constitution precise control and is subject to many researchers' favor.Hydrothermal method is in special closed reactor (autoclave), take the fluid such as water or organic solvent as reactive material, by reaction system being heated to critical temperature (or approaching critical temperature), create a high-temperature high-voltage reaction environment, impel reaction to carry out in liquid phase or gas phase, make originally indissoluble or insoluble material solvent recrystallization, then through separating and thermal treatment obtains a kind of effective ways of product.Hydrothermal method has the following advantages: (1) is warm (generally between 120 ~ 220 ℃) liquid phase control in adopting, and energy consumption is relatively low, and suitability is wide, both can be used for the nanoparticle preparation that size is less, 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, productive rate is high, thing mutually evenly, high, the well-crystallized of purity, and shape size is controlled; (3), in water-heat process, can, by regulating temperature of reaction, pressure, time, pH value, precursor and tensio-active agent etc., reach the object 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 poisonous system, can reduce environmental pollution.

But rarely have report but utilize hydrothermal method to prepare indium selenide, only have 2011, the people such as poplar have gone out γ-In with ethanol as solvent Hydrothermal Synthesis at 220 ℃ ₂se ₃microballoon, the diameter of this ball is at 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 defect existing in 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, by indium nitrate, selenium powder solvent thermal building-up reactions in reactor, then uses absolute ethanol washing, and centrifugation makes after dry.Infer from growth mechanism, the method can be applicable to the preparation of other selenium metallic compound nano materials.

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

Steps A, take 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, add oleic acid stir 30min, the volume of wherein said oleic acid accounts for 60% ~ 80% of reactor;

Step C, reactor is reacted to 12h ~ 24h at 190 ℃ ~ 220 ℃, be then 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 reacts 24h at 200 ℃.

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

α-the In being prepared from according to above-mentioned solvent process for thermosynthesizing ₂se ₃nanometer bouquet, 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 ₃nano flower spherical diameter is at 1 ~ 2 micron, and the nanometer sheet that is 13 ~ 15nm by thickness forms.

beneficial effect

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

Accompanying drawing explanation

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

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

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

Flower ball-shaped indium selenide transmission electron microscope picture (TEM) prepared by Fig. 4.

Embodiment

Below in conjunction with embodiment, the present invention is described in detail, 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 respectively 0.2292g indium nitrate with electronic balance, 0.0158g selenium powder, 0.0352g xitix, 30ml oleic acid is in 50ml reactor, and magneton stirs 30 minutes;

(2) reactor sealing is put into 200 ℃ of baking oven constant temperature 24 hours, then naturally cool to room temperature, use absolute ethanol washing 8 times, the dry black flower ball-shaped indium selenide that obtains 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 the material that obtains and the card 34-1313 of JCPDS (JCPDS) match, and in this peak, there is no the peak of other impurity, 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, bouquet dispersiveness is relatively good, and surface ratio is more coarse, and diameter is greatly about 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 made up of for the nanometer sheet of 15 nanometers left and right thickness.

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

Embodiment 2:

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

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

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

Embodiment 3:

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

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

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

Embodiment 4:

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

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

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

Embodiment 5:

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

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

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

Embodiment 6:

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

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

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

Claims (5)

1. a α-In ₂se ₃nanometer bouquet solvent process for thermosynthesizing, is take oleic acid as solvent, and xitix is reductive agent, by indium nitrate, selenium powder solvent thermal building-up reactions in reactor, then use absolute ethanol washing, and centrifugation makes after dry, it is characterized in that, described solvent thermal building-up reactions comprises the steps:

Steps A, take 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, add oleic acid stir 30min, the volume of wherein said oleic acid accounts for 60% ~ 80% of reactor;

Step C, reactor is reacted to 12h ~ 24h at 190 ℃ ~ 220 ℃, be then cooled to room temperature.

2. α-according to claim 1 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 reacts 24h at 200 ℃.

3. α-In that method according to claim 1 and 2 is prepared from ₂se ₃nanometer bouquet.

4. α-according to claim 3 ₂se ₃nanometer bouquet, is characterized in that described bouquet diameter is at 1 ~ 2 micron.

5. α-according to claim 3 ₂se ₃nanometer bouquet, is characterized in that the nanometer sheet that described bouquet is 13 ~ 15nm by thickness is formed.

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