A synthesis process of γ-phase indium selenide

Abstract

The present invention discloses a synthesis process of γ-phase indium selenide, which relates to the technical field of indium selenide. It includes two main steps: synthesizing In 4 Se 3 powder and further preparing γ-phase indium selenide. High-purity selenium powder and indium powder are used to synthesize In 4 Se 3 powder in an atmospheric-pressure tubular synthesis furnace; the In 4 Se 3 powder reacts with selenium powder again to obtain high-purity γ-phase indium selenide. By optimizing the raw material ratio, atmosphere protection, ball milling and mixing, and resin carbon adsorption, the present invention effectively reduces the introduction of impurities, prevents selenium volatilization, and improves the phase composition homogeneity and purity of indium selenide. The prepared γ-phase indium selenide has excellent optoelectronic properties and thermal stability, and can be widely applied in the fields of photoelectric conversion and thermoelectric materials.

Description

Technical Field

[0001] The present invention relates to the technical field of indium selenide, in particular to the synthesis process of γ-phase indium selenide. Background Art

[0002] Indium selenide (In 2 Se 3 ) is an important wide-bandgap semiconductor material with excellent optoelectronic and thermoelectric properties, and is widely used in fields such as photovoltaic devices, thermoelectric materials, photodetectors, and infrared optical devices. Different crystal phases of indium selenide (including α-phase, β-phase, γ-phase, and δ-phase) are suitable for different practical applications due to the differences in their crystal structures and physicochemical properties.

[0003] Among them, γ-phase indium selenide has important value in the fields of high-performance optoelectronic materials and thermoelectric conversion due to its specific energy band structure and thermal stability. The energy gap of γ-In 2 Se 3 is approximately 1.9 eV. The crystal structure of indium selenide depends on the preparation method. For example, K. J. Chang et al. pointed out in "Growth of single-phase In 2 Se 3 by using metal organicchemical vapor deposition with dual-source precursors" that γ-In 2 Se 3 can be prepared by trimethylindium (InMe 3 ) and hydrogen selenide (H 2 Se) through metal organic chemical vapor deposition.

[0004] Chemical vapor deposition generates indium selenide thin films through the gas-phase reaction of selenium and indium compounds. This method can achieve the preparation of high-purity materials and is suitable for the growth of large-area thin films. However, this method requires high equipment requirements, the process is complex, and it is suitable for the preparation of thin films rather than powder materials.

[0005] In addition, there are still many problems in the synthesis of high-purity γ-phase indium selenide:

[0006] Selenium volatilization problem: Selenium is prone to volatilization under high-temperature conditions, resulting in an imbalance in the stoichiometric ratio of selenium and indium during the reaction, thereby affecting the phase composition and purity of the product.

[0007] Generation of secondary phases: The polycrystalline phase characteristics of indium selenide make it easy to generate other crystal phases (such as α-phase or δ-phase) during the synthesis process, affecting the purity and material properties of the γ-phase.

[0008] Impurity problem: The purity of selenium and indium materials may not be sufficient to meet the high-purity requirements of semiconductor materials. Even raw materials with a nominal high purity (such as 4N or 4.5N) may contain trace amounts of metal impurities (such as iron, copper, nickel, etc.) and non-metal impurities (such as oxides or sulfides); selenium is extremely easy to oxidize to form selenium dioxide (SeO 2 ) in a high-temperature environment, and these oxides may remain in the product during the reaction process, forming selenium oxide impurities, which in turn affect the semiconductor properties of the product. Summary of the Invention

[0009] Based on the above background, it is of great scientific research and industrial value to develop a simple, efficient, low-energy-consuming, high-purity, uniform phase composition and large-scale production suitable γ-phase indium selenide synthesis process by this method. This method solves the problems of impurity introduction and secondary phase generation, while ensuring the crystal phase purity and particle size uniformity of the product to meet the requirements of high-performance optoelectronic materials.

[0010] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0011] A synthesis process of γ-phase indium selenide, characterized by comprising the following steps:

[0012] S1: Synthesize In 4 Se 3 powder:

[0013] Weigh 46.44 - 61.92 parts of selenium powder and 9 - 12 parts of indium powder according to mass parts;

[0014] Transfer the above selenium powder and indium powder into an atmospheric pressure tubular synthesis furnace, displace the air with an inert gas, and control the gas flow rate to be 0.1 - 1 L / min;

[0015] Crush the reaction product and perform air flow pulverization treatment to obtain In 4 Se 3 powder with a particle size of 10 - 45 μm;

[0016] S2: Synthesize γ-phase indium selenide:

[0017] Add 30.96 - 41.28 parts of selenium powder to the prepared In 4 Se 3 powder, and ball-mill and mix to obtain a mixed powder;

[0018] Transfer the mixed powder into an atmospheric pressure tubular synthesis furnace, add 2 - 6 parts of resin carbon, displace the air with an inert gas, and control the gas flow rate to be 0.1 - 1 L / min;

[0019] Naturally cool to room temperature, take out the reaction product, and filter to obtain γ-phase indium selenide;

[0020] The method for preparing the resin carbon in step S2 is:

[0021] (1) preparing the aqueous phase: adding 1000-1200 parts of water by weight to a reaction container, heating to 60-70° C., adding 1-3 parts of gelatin, 1-3 parts of sodium chloride, and 0.01-0.05 parts of methylene blue solution, stirring until completely dissolved and mixed uniformly, to prepare the aqueous phase for use;

[0022] (2) preparing the oil phase: adding 30-50 parts by weight of divinylbenzene, 0.2-0.5 parts by weight of methacryl cage silsesquioxane (CAS: 204591-17-2), 0.02-0.3 parts by weight of 4-vinylbenzocyclobutene, 5-8 parts by weight of styrene, 20-30 parts by weight of paraffin wax, and 0.4-0.8 parts by weight of benzoyl peroxide into a reaction container, stirring until uniform, to prepare the oil phase for later use;

[0023] (3) Synthesizing white resin balls: slowly add the prepared oil phase to the water phase, stir, heat to 80-100°C, stir for 7-15 hours to form resin, filter, dry, put the resin into 1000-1200 parts of gasoline, stir at 80-100°C for 4-7 hours, filter, dry, and obtain microporous white resin balls;

[0024] (4) Resin carbonization: Take the microporous resin white ball of step (3) and put it into the carbonization furnace, introduce nitrogen at a rate of 70-80cm3 / min, increase the temperature to 500°C at a rate of 15°C / min, keep it warm for 20-30min, continue to increase the temperature to 700°C at a rate of 15°C / min, keep it warm for 5-10min, continue to increase the temperature to 800°C at a rate of 15°C / min, keep it warm for 5-10min, turn off the nitrogen and introduce water vapor, keep it warm for 60-100min, cool naturally, and obtain resin carbon.

[0025] Preferably, the purity of the selenium powder and indium powder is not less than 99.99%.

[0026] Preferably, the inert gas in S1 and S2 is selected from one of nitrogen, argon or helium.

[0027] Preferably, the S1 is heated in two stages:

[0028] In the first stage, the temperature is raised to 180-200°C at a rate of 1-3°C / min and kept constant for 3-5 hours to allow selenium and indium to react fully and inhibit selenium volatilization;

[0029] In the second stage, the temperature is raised to 440-460℃, the heating rate is 2-5℃ / min, and the temperature is kept constant for 3-5 hours to completely convert the free selenium into In. 4 Se 3 .

[0030] Preferably, the ball milling and mixing parameters in step S2 are as follows:

[0031] Mass ratio of material to balls: 1:3 to 1:5;

[0032] Ball milling time: 10 - 30 minutes;

[0033] Ball milling speed: 150 - 300 rpm;

[0034] Ball milling atmosphere: nitrogen or argon;

[0035] Type of ball mill: planetary ball mill or horizontal drum ball mill.

[0036] Preferably, the heating reaction in step S2 is carried out in two stages:

[0037] In the first stage, the temperature is raised to 190 - 210 °C at a heating rate of 1 - 3 °C / min and kept at a constant temperature for 1.5 - 2.5 hours to allow Se to react with In. 4 Se 3 React;

[0038] In the second stage, the temperature is raised to 590 - 610 °C at a heating rate of 2 - 5 °C / min and kept at a constant temperature for 3.5 - 4.5 hours to completely convert indium selenide into the γ phase.

[0039] Analysis of mechanism and technical effects:

[0040] 1. Structure and function of allyl silsesquioxane

[0041] Allyl silsesquioxane is a cage - shaped compound containing eight carbon - carbon double bonds. This structure endows it with high reactivity and enables it to be used as a super cross - linker.

[0042] Due to the presence of its eight carbon - carbon double bonds, allyl silsesquioxane can provide new cross - linking nodes, thus optimizing the microporous structure of resin carbon. This optimized microporous structure is more conducive to adsorbing gas impurities and improving the adsorption performance of the material.

[0043] Technical effect: Through the cross - linking effect of allyl silsesquioxane, the microporous structure of resin carbon is improved, enhancing its ability to adsorb impurities, which in turn contributes to the preparation of high - purity γ - phase indium selenide.

[0044] 2. Structure and function of benzocyclobutene functional group

[0045] Structural features: 4 - vinylbenzocyclobutene is a compound with a rigid structure, and the benzocyclobutene functional group in its structure provides high strength and thermal stability.

[0046] Enhancing effect: The rigid structure of 4-vinylbenzocyclobutene can improve the strength of the resin white balls, which is crucial for the subsequent calcination process. During the calcination process, the resin white balls are transformed into resin carbon, helping to maintain the strength of the carbon material.

[0047] Technical effect: By introducing 4-vinylbenzocyclobutene, the strength of the resin carbon is significantly improved, which is particularly important for its applications in high-temperature and high-pressure environments. At the same time, it also helps to improve the wear resistance and chemical corrosion resistance of the resin carbon.

[0048] 3. Comprehensive analysis

[0049] Synergistic effect: The combined use of allyl cage silsesquioxane and benzocyclobutene functional groups can optimize the microporous structure and enhance the strength in the resin carbon material, thus achieving better adsorption and mechanical properties.

[0050] Application fields: This composite material has broad application prospects in fields such as adsorbing impurities and preparing high-purity γ-phase indium selenide.

[0051] Technical effect

[0052] Compared with the traditional process, the present invention effectively avoids the volatilization loss of selenium through staged heating reactions, ensuring the high purity and stability of indium selenide. By controlling the raw material purity and adding resin carbon for adsorption, the prepared γ-phase indium selenide product has the characteristics of high purity (>99.99%) and uniform phase composition, significantly improving its optoelectronic properties. Specific implementation manners

[0053] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0054] Except for special regulations otherwise, the reagents used in the embodiments of the present invention can all be obtained by commercial purchase. Among them, the purity of selenium powder and indium powder in this method is both 99.99%. The selenium powder is purchased from Shanghai Kemi Chemical Technology Co., Ltd.; the indium powder is purchased from Hunan Zhongcai Shengte New Materials Technology Co., Ltd.

[0055] The embodiments are detected in the following ways:

[0056] X-ray diffraction (XRD) analysis

[0057] Purpose: To detect the crystal phase composition of the product, confirm the formation of γ-phase indium selenide and the content of secondary phases.

[0058] Equipment: D / MAX 2500 X-ray diffractometer.

[0059] Parameters: Cu Kα ray, scanning range 10° - 80°, scanning rate 0.02° / s.

[0060] Example 1

[0061] A synthesis process of γ-phase indium selenide, characterized by comprising the following steps:

[0062] S1: Synthesize In 4 Se 3 powder:

[0063] Weigh 46.44 g of selenium powder and 9 g of indium powder;

[0064] Transfer the above selenium powder and indium powder into an atmospheric pressure tubular synthesis furnace, displace the air with an inert gas, and control the gas flow rate to be 0.3 L / min;

[0065] Crush the reaction product and perform air flow pulverization treatment to obtain In 4 Se 3 powder with a particle size of 10 to 45 μm.

[0066] S2: Synthesize γ-phase indium selenide:

[0067] Add 30.96 g of selenium powder to the prepared In 4 Se 3 powder, and ball-mill and mix to obtain a mixed powder;

[0068] Transfer the mixed powder into an atmospheric pressure tubular synthesis furnace, add 2 g of resin carbon, displace the air with an inert gas, and control the gas flow rate to be 0.3 L / min;

[0069] Naturally cool to room temperature, take out the reaction product, filter to obtain γ-phase indium selenide;

[0070] The preparation method of the resin carbon in step S2 is as follows:

[0071] (1) Prepare the aqueous phase: Add 1000 g of water to a reaction vessel, heat to 60 °C, add 1 g of gelatin, 1 g of sodium chloride, 0.01 g of methylene blue solution, and stir until completely dissolved and mixed evenly to obtain the aqueous phase for standby;

[0072] (2) Prepare the oil phase: Add 30 g of divinylbenzene, 0.2 g of methylpropenylcuboctasilsesquioxane (CAS: 204591-17-2), 0.02 g of 4-vinylbenzocyclobutene, 5 g of styrene, 20 g of paraffin, and 0.4 g of benzoyl peroxide to a reaction vessel, and stir until uniform to obtain the oil phase for standby;

[0073] (3) Synthesizing white resin balls: slowly add the prepared oil phase to the water phase, stir, heat to 80°C, stir for 7 hours to form a resin, filter, dry, put the resin into 1000g gasoline, stir at 80°C for 4 hours, filter, dry, and obtain microporous white resin balls;

[0074] (4) Resin carbonization: Take the microporous resin white ball from step (3) and put it into the carbonization furnace at 70 cm 3 / min nitrogen gas was introduced, the temperature was raised to 500°C at a rate of 15°C / min, and kept warm for 20 min. The temperature was further raised to 700°C at a rate of 15°C / min, and kept warm for 5 min. The temperature was further raised to 800°C at a rate of 15°C / min, and kept warm for 5 min. The nitrogen gas was turned off and water vapor was introduced, and the temperature was kept warm for 60 min. The resin carbon was obtained by natural cooling.

[0075] The inert gas in S1 and S2 is selected from nitrogen.

[0076] The S1 performs heating reaction in two stages:

[0077] In the first stage, the temperature is raised to 180°C at a rate of 1°C / min and kept constant for 3 hours to allow selenium and indium to react fully and inhibit selenium volatilization;

[0078] In the second stage, the temperature is raised to 440°C at a rate of 2°C / min and kept constant for 3 hours to completely convert free selenium into In. 4 Se 3 .

[0079] The ball milling mixing parameters in step S2 are:

[0080] Material to ball mass ratio: 1:3;

[0081] Ball milling time: 10 minutes;

[0082] Ball milling speed: 150 rpm;

[0083] Ball milling atmosphere: nitrogen;

[0084] Ball mill type: planetary ball mill.

[0085] The heating reaction is carried out in two stages in step S2:

[0086] In the first stage, the temperature was raised to 190°C at a rate of 1°C / min and kept constant for 1.5 hours to allow selenium to react with In. 4 Se 3 reaction;

[0087] In the second stage, the temperature is raised to 590°C at a heating rate of 2°C / min and maintained at this temperature for 3.5 hours to completely convert indium selenide into the γ phase.

[0088] After detection, in the product indium selenide of this example, the intensity ratio of the diffraction peak of the γ phase is 97.9%, and the intensity ratio of the diffraction peak of the secondary phase is 2.1%.

[0089] Example 2

[0090] A synthesis process of γ-phase indium selenide, characterized by comprising the following steps:

[0091] S1: Synthesize In 4 Se 3 powder:

[0092] Weigh 51.6 g of selenium powder and 10 g of indium powder;

[0093] Transfer the above selenium powder and indium powder into an atmospheric pressure tube furnace, displace the air with an inert gas, and control the gas flow rate to be 0.6 L / min;

[0094] Crush the reaction product and perform air-flow pulverization treatment to obtain In 4 Se 3 powder with a particle size of 10 to 45 μm;

[0095] S2: Synthesize γ-phase indium selenide:

[0096] Add 34.4 g of selenium powder to the prepared In 4 Se 3 powder and ball-mill and mix to obtain a mixed powder;

[0097] Transfer the mixed powder into an atmospheric pressure tube furnace, add 4 g of resin carbon, displace the air with an inert gas, and control the gas flow rate to be 0.5 L / min;

[0098] Naturally cool to room temperature, take out the reaction product, filter, and obtain γ-phase indium selenide;

[0099] The preparation method of the resin carbon in the step S2 is as follows:

[0100] (1) Prepare the aqueous phase: Add 1100 g of water to a reaction vessel, heat to 65 °C, add 2 g of gelatin, 2 g of sodium chloride, and 0.03 g of methylene blue solution, stir until completely dissolved and mixed evenly, and prepare the aqueous phase for standby;

[0101] (2) Prepare the oil phase: Add 40 g of divinylbenzene, 0.3 g of methylallyl silsesquioxane (CAS: 204591-17-2), 0.1 g of 4-vinylbenzocyclobutene, 6 g of styrene, 25 g of paraffin, and 0.6 g of benzoyl peroxide to a reaction vessel, stir until uniform, and prepare the oil phase for standby;

[0102] (3) Synthetic resin white balls: Slowly add the prepared oil phase to the water phase, stir, heat up to 90 °C, and stir for 10 hours to form resin. Filter and dry the resin. Put the resin into 1100 g of gasoline, stir at 90 °C for 5 hours, filter, and dry to obtain microporous resin white balls;

[0103] (4) Resin carbonization: Take the microporous resin white balls from step (3) and put them into a carbonization furnace. Pass nitrogen at a rate of 75 cm 3 / min, heat up to 500 °C at a rate of 15 °C / min, hold for 25 min, continue to heat up to 700 °C at a rate of 15 °C / min, hold for 7 min, continue to heat up to 800 °C and hold for 7 min. Turn off the nitrogen and pass in steam, hold for 80 min, and cool naturally to obtain resin carbon.

[0104] The inert gas in S1 and S2 is selected from nitrogen.

[0105] The heating reaction in S1 is carried out in two stages:

[0106] In the first stage, heat up to 190 °C at a heating rate of 2 °C / min and hold for 4 hours to allow selenium and indium to react fully and inhibit selenium volatilization;

[0107] In the second stage, heat up to 450 °C at a heating rate of 3 °C / min and hold for 4 hours to completely convert free selenium into In 4 Se 3 .

[0108] The ball milling mixing parameters in step S2 are as follows:

[0109] Mass ratio of material to balls: 1:4;

[0110] Ball milling time: 20 minutes;

[0111] Ball milling speed: 200 rpm;

[0112] Ball milling atmosphere: nitrogen;

[0113] Type of ball mill: planetary ball mill.

[0114] The heating reaction in step S2 is carried out in two stages:

[0115] In the first stage, heat up to 200 °C at a heating rate of 2 °C / min and hold for 2 hours to allow selenium and In 4 Se 3 to react;

[0116] In the second stage, heat up to 600 °C at a heating rate of 3 °C / min and hold for 4 hours to completely convert indium selenide into the γ phase.

[0117] After detection, in the product indium selenide of this example, the intensity ratio of the γ-phase diffraction peak is 98.1%, and the intensity ratio of the secondary-phase diffraction peak is 1.9%.

[0118] Example 3

[0119] A synthesis process of γ-phase indium selenide, characterized by comprising the following steps:

[0120] S1: Synthesize In 4 Se 3 powder:

[0121] Weigh 51.6 g of high-purity selenium powder and 10 g of indium powder;

[0122] Transfer the above selenium powder and indium powder into an atmospheric-pressure tubular synthesis furnace, displace the air with an inert gas, and control the gas flow rate to be 0.8 L / min;

[0123] Crush the reaction product and perform air-flow pulverization treatment to obtain In 4 Se 3 powder with a particle size of 10 to 45 μm;

[0124] S2: Synthesize γ-phase indium selenide:

[0125] Add 34.4 g of selenium powder to the prepared In 4 Se 3 powder and perform ball-milling mixing;

[0126] Transfer the mixed powder into an atmospheric-pressure tubular synthesis furnace, add 4 g of resin carbon, displace the air with an inert gas, and control the gas flow rate to be 0.8 L / min;

[0127] Naturally cool to room temperature, take out the reaction product, and filter to obtain γ-phase indium selenide;

[0128] The preparation method of the resin carbon in the step S2 is as follows:

[0129] (1) Prepare the aqueous phase: Add 1100 g of water to a reaction vessel, heat to 65 °C, add 2 g of gelatin, 2 g of sodium chloride, and 0.03 g of methylene blue solution, stir until completely dissolved and mixed evenly, and prepare the aqueous phase for later use;

[0130] (2) Prepare the oil phase: Add 40 g of divinylbenzene, 0.4 g of methylpropenylcage silsesquioxane (CAS: 204591-17-2), 0.2 g of 4-vinylbenzocyclobutene, 7 g of styrene, 25 g of paraffin, and 0.6 g of benzoyl peroxide to a reaction vessel, stir until uniform, and prepare the oil phase for later use;

[0131] (3) Synthetic resin white balls: Slowly add the prepared oil phase to the water phase, stir, heat up to 90 °C, stir for 12 hours to form resin, filter, dry, put the resin into 1100 g of gasoline, stir at 90 °C for 6 hours, filter, dry, and obtain microporous resin white balls;

[0132] (4) Resin carbonization: Put the microporous resin white balls from step (3) into a carbonization furnace, introduce nitrogen at a rate of 75 cm 3 / min, heat up to 500 °C at a rate of 15 °C / min, hold for 25 min, continue to heat up to 700 °C at a rate of 15 °C / min, hold for 8 min, continue to heat up to 800 °C and hold for 8 min, turn off the nitrogen and introduce steam, hold for 80 min, and cool naturally to obtain resin carbon.

[0133] The inert gas in S1 and S2 is selected from nitrogen.

[0134] The heating reaction in S1 is carried out in two stages:

[0135] In the first stage, heat up to 190 °C at a heating rate of 2 °C / min, keep the temperature constant for 4 hours to make selenium and indium fully react and inhibit selenium volatilization;

[0136] In the second stage, heat up to 450 °C at a heating rate of 4 °C / min, keep the temperature constant for 4 hours to completely convert free selenium into In 4 Se 3 .

[0137] The ball milling mixing parameters in step S2 are as follows:

[0138] Mass ratio of material to balls: 1:4;

[0139] Ball milling time: 20 minutes;

[0140] Ball milling speed: 250 rpm;

[0141] Ball milling atmosphere: nitrogen;

[0142] Type of ball mill: planetary ball mill.

[0143] The heating reaction in step S2 is carried out in two stages:

[0144] In the first stage, heat up to 200 °C at a heating rate of 2 °C / min, keep the temperature constant for 2 hours to make selenium and In 4 Se 3 react;

[0145] In the second stage, heat up to 500 °C at a heating rate of 4 °C / min, keep the temperature constant for 4 hours to completely convert indium selenide into the γ phase.

[0146] After detection, in the product indium selenide of this example, the intensity ratio of the diffraction peak of the γ phase is 98.4%, and the intensity ratio of the diffraction peak of the secondary phase is 1.6%.

[0147] Example 4

[0148] A synthesis process of γ-phase indium selenide, characterized by comprising the following steps:

[0149] S1: Synthesize In 4 Se 3 powder:

[0150] Weigh 61.92 g of selenium powder and 12 g of indium powder;

[0151] Transfer the above selenium powder and indium powder into an atmospheric pressure tubular synthesis furnace, displace the air with an inert gas, and control the gas flow rate to be 1 L / min;

[0152] Crush the reaction product, and perform air flow pulverization treatment to obtain In 4 Se 3 powder with a particle size of 10 to 45 μm;

[0153] S2: Synthesize γ-phase indium selenide:

[0154] Add 41.28 g of selenium powder to the In 4 Se 3 powder prepared above, and perform ball milling and mixing to obtain a mixed powder;

[0155] Transfer the mixed powder into an atmospheric pressure tubular synthesis furnace, add 6 g of resin carbon, displace the air with an inert gas, and control the gas flow rate to be 1 L / min;

[0156] Naturally cool to room temperature, take out the reaction product, and filter to obtain γ-phase indium selenide;

[0157] The preparation method of the resin carbon in the step S2 is as follows:

[0158] (1) Prepare the aqueous phase: Add 1200 g of water to a reaction vessel, heat to 70 °C, add 3 g of gelatin, 3 g of sodium chloride, and 0.05 g of methylene blue solution, and stir until completely dissolved and mixed evenly to obtain the aqueous phase for standby;

[0159] (2) Prepare the oil phase: Add 50 g of divinylbenzene, 0.5 g of methylpropenylcaged sesquisiloxane (CAS: 204591-17-2), 0.3 g of 4-vinylbenzocyclobutene, 8 g of styrene, 30 g of paraffin, and 0.8 g of benzoyl peroxide to a reaction vessel, and stir until uniform to obtain the oil phase for standby;

[0160] (3) Synthetic resin white balls: Slowly add the prepared oil phase to the water phase, stir, heat up to 100 °C, stir for 15 hours to form resin, filter, dry, put the resin into 1200 g of gasoline, stir at 100 °C for 7 hours, filter, dry, and obtain microporous resin white balls;

[0161] (4) Resin carbonization: Put the microporous resin white balls obtained in step (3) into a carbonization furnace, introduce nitrogen at a rate of 80 cm3 / min, heat up to 500 °C at a rate of 15 °C / min, keep warm for 30 min, continue to heat up to 700 °C at a rate of 15 °C / min, keep warm for 10 min, continue to heat up to 800 °C at a rate of 15 °C / min and keep warm for 10 min, turn off the nitrogen and introduce steam, keep warm for 100 min, and cool naturally to obtain resin carbon.

[0162] The inert gas in S1 and S2 is selected from nitrogen.

[0163] The heating reaction in S1 is carried out in two stages:

[0164] In the first stage, heat up to 200 °C at a heating rate of 3 °C / min, keep the temperature constant for 5 hours to make selenium and indium react fully and inhibit selenium volatilization;

[0165] In the second stage, heat up to 460 °C at a heating rate of 5 °C / min, keep the temperature constant for 5 hours to make free selenium completely converted into In 4 Se 3 .

[0166] The ball milling mixing parameters in step S2 are as follows:

[0167] Mass ratio of material to balls: 1:5;

[0168] Ball milling time: 30 minutes;

[0169] Ball milling speed: 300 rpm;

[0170] Ball milling atmosphere: nitrogen;

[0171] Type of ball mill: planetary ball mill.

[0172] The heating reaction in step S2 is carried out in two stages:

[0173] In the first stage, heat up to 210 °C at a heating rate of 3 °C / min, keep the temperature constant for 2.5 hours to make selenium and In 4 Se 3 react;

[0174] In the second stage, heat up to 610 °C at a heating rate of 5 °C / min, keep the temperature constant for 4.5 hours to make indium selenide completely converted into the γ phase.

[0175] Upon detection, in the product indium selenide of this example, the intensity ratio of the γ-phase diffraction peak is 98.9%, and the intensity ratio of the secondary-phase diffraction peak is 1.1%.

[0176] Comparative Example 1

[0177] The difference between this comparative example and Example 1 is only that: resin carbon is not added.

[0178] Upon detection, in the product indium selenide of this example, the intensity ratio of the γ-phase diffraction peak is 94.1%, and the intensity ratio of the secondary-phase diffraction peak is 5.9%.

[0179] Comparative Example 2

[0180] The difference between this comparative example and Example 1 is only that: methacryloylcaged silsesquioxane is not added during the preparation of resin carbon.

[0181] Upon detection, in the product indium selenide of this example, the intensity ratio of the γ-phase diffraction peak is 95.4%, and the intensity ratio of the secondary-phase diffraction peak is 4.6%.

[0182] Comparative Example 3

[0183] The difference between this comparative example and Example 1 is only that: 4-vinylbenzocyclobutene is not added during the preparation of resin carbon.

[0184] Upon detection, in the product indium selenide of this example, the intensity ratio of the γ-phase diffraction peak is 95.1%, and the intensity ratio of the secondary-phase diffraction peak is 4.9%.

[0185] From the above test results, it can be seen that the present invention has significant technical advantages in synthesizing high-purity γ-phase indium selenide.

[0186] The above are the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle described in the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A synthesis process of γ-phase indium selenide, characterized in that: The following steps are involved: S1: Synthesis of In4Se3 powder: Weigh 46.44-61.92 parts of selenium powder and 9-12 parts of indium powder according to mass proportions; The selenium powder and indium powder are transferred to a normal pressure tubular synthesis furnace, and the air is replaced by an inert gas, and the gas flow rate is controlled to be 0.1-1 L / min; The reaction product is crushed and treated by air flow pulverization to obtain In4Se3 powder with a particle size of 10-45 μm; S2: Synthesis of γ-phase InSe: Add 30.96-41.28 parts of selenium powder to the prepared In4Se3 powder, and mix by ball milling to obtain a mixed powder; The mixed powder is transferred to a normal pressure tubular synthesis furnace, 2-6 parts of resin carbon are added, the air is replaced by inert gas, and the gas flow rate is controlled to be 0.1-1 L / min; Cool naturally to room temperature, take out the reaction product, filter it, and obtain γ-phase indium selenide; The resin carbon preparation uses acryl cage-type silsesquioxane as a super cross-linking agent; The method for preparing the resin carbon in step S2 is: (1) preparing the aqueous phase: adding 1000-1200 parts of water by weight to a reaction container, heating to 60-70° C., adding 1-3 parts of gelatin, 1-3 parts of sodium chloride, and 0.01-0.05 parts of methylene blue solution, stirring until completely dissolved and mixed uniformly, to prepare the aqueous phase for use; (2) preparing an oil phase: adding 30-50 parts by weight of divinylbenzene, 0.2-0.5 parts by weight of methacryl cage silsesquioxane, 0.02-0.3 parts by weight of 4-vinylbenzocyclobutene, 5-8 parts by weight of styrene, 20-30 parts by weight of paraffin wax, and 0.4-0.8 parts by weight of benzoyl peroxide into a reaction container, stirring until uniform, to prepare an oil phase for later use; (3) Synthesizing white resin balls: slowly add the prepared oil phase to the water phase, stir, heat to 80-100°C, stir for 7-15 hours to form resin, filter, dry, put the resin into 1000-1200 parts of gasoline, stir at 80-100°C for 4-7 hours, filter, dry, and obtain microporous white resin balls; (4) Resin carbonization: Take the microporous resin white ball from step (3) and put it into the carbonization furnace at 70-80 cm 3 / min, introduce nitrogen, increase the temperature to 500°C at a rate of 15°C / min, keep warm for 20-30min, continue to increase the temperature to 700°C at a rate of 15°C / min, keep warm for 5-10min, continue to increase the temperature to 800°C at a rate of 15°C / min, keep warm for 5-10min, turn off the nitrogen, introduce water vapor, keep warm for 60-100min, cool naturally, and obtain resin carbon.

2. The synthesis process of γ-phase indium selenide according to claim 1, characterized in that: The purity of the selenium powder and indium powder is not less than 99.99%.

3. The synthesis process of γ-phase indium selenide according to claim 1, characterized in that: The inert gas in S1 and S2 is selected from one of nitrogen, argon or helium.

4. The synthesis process of γ-phase indium selenide according to claim 1, characterized in that: The S1 performs heating reaction in two stages: In the first stage, the temperature is raised to 180-200°C at a rate of 1-3°C / min and kept constant for 3-5 hours to allow selenium and indium to react fully and inhibit selenium volatilization; In the second stage, the temperature is raised to 440-460°C at a rate of 2-5°C / min and maintained at a constant temperature for 3-5 hours to completely convert free selenium into In4Se3.

5. The synthesis process of γ-phase indium selenide according to claim 1, characterized in that: The ball milling mixing parameters in step S2 are: Material to ball mass ratio: 1:3 to 1:5; Ball milling time: 10-30 minutes; Ball mill speed: 150-300 rpm; Ball milling atmosphere: nitrogen or argon; Ball mill type: planetary ball mill or horizontal drum ball mill.

6. The synthesis process of γ-phase indium selenide according to claim 1, characterized in that: The heating reaction is carried out in two stages in step S2: In the first stage, the temperature is raised to 190-210°C at a rate of 1-3°C / min and kept constant for 1.5-2.5 hours to allow selenium to react with In4Se3; In the second stage, the temperature is raised to 590-610°C at a heating rate of 2-5°C / min and maintained at a constant temperature for 3.5-4.5 hours to completely convert indium selenide into the γ phase.