A method for preparing Sb2Se3 alloy
By controlling the temperature and flowing into Se liquid in the quartz reactor, the problems of poor uniformity and high cost in the preparation of antimony selenide are solved, and efficient and safe preparation of antimony selenide is achieved, and the preparation cost is reduced.
Patent Information
- Application Number
- CN202211329829.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-10-27
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2042-10-27
AI Technical Summary
In the preparation of antimony selenide (Sb2Se3), the low boiling point of selenide and the melting point of antimony are close, resulting in poor selenium volatility and component uniformity in high-temperature mixing reactions, and vacuum sealing leads to high cost and inconvenient reuse.
Using a special quartz reactor, by controlling the melting and mixing reaction of Sb and Se at different temperatures, Sb is first melted, and then the Se liquid is slowly flowed into the Sb liquid to react. The specific heating procedure and sway homogenization treatment are used to avoid Se volatility. And improve component uniformity without vacuum sealing to reduce costs.
It effectively avoids the volatility of Se, improves component uniformity and yield, reduces preparation costs, ensures production safety, and enables the quartz reactor to be reused multiple times.
Smart Images
Figure CN115787095B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of alloy material preparation, and specifically relates to a method for preparing a Sb2Se3 alloy. Background Art
[0002] Antimony selenide (Sb2Se3) is a binary compound semiconductor. Its constituent elements, antimony and selenium, are low in toxicity and have abundant reserves. Antimony selenide has a suitable band gap (~1.2eV) and excellent light absorption properties (absorption coefficient>10 5 cm -1 ), has attracted much attention in the optoelectronic field in recent years. Antimony selenide crystals have a unique quasi-one-dimensional ribbon-like crystal structure. The atoms within the band are connected by covalent bonds, while the bands are stacked together by van der Waals forces, which makes the carrier transmission rate within the band much greater than the transmission rate between bands. Therefore, antimony selenide materials have strong anisotropy in optical and electrical properties.
[0003] At present, the solar cell structures with antimony selenide as the light absorption layer reported in the literature mainly include sensitized solar cells and planar structure solar cells. In the planar structure, antimony selenide is often used as a p-type semiconductor layer to form a heterojunction with n-type cadmium sulfide (CdS), titanium dioxide (TiO2) or organic matter. In addition, antimony selenide is also widely used in the field of optoelectronics, so the low-cost and high-yield preparation of Sb2Se3 materials is of great significance.
[0004] Patent CN 113235166A discloses that the synthesis of antimony selenide polycrystalline raw materials is to mix antimony particles and selenium powder in a ratio of 1:1.02 to 1:1.05, pour them into a quartz tube, and bake them while vacuuming. -3 Pa or less, and then the sealed quartz tube is placed in a tube furnace, heated to 550-800°C and kept warm for 6-12 hours, and then cooled to room temperature to obtain a polycrystalline ingot. Patent CN112201725A discloses that the raw materials are placed in a swing mixing furnace, kept at 650°C and mixed for 24 hours to obtain antimony selenide crystals with a purity of 99.99%. The above-mentioned prior arts are all directly mixing the antimony and selenium raw materials at high temperature. However, due to the low boiling point of selenium, which is close to the melting point of antimony, the direct high-temperature mixing reaction will cause selenium volatilization, resulting in poor component uniformity and reduced yield; and due to the density difference between Sb and Se, the direct mixing reaction will also result in poor component uniformity. In addition, the existing methods for the synthesis of antimony selenide are all carried out under vacuum conditions, and vacuum sealing is required. The quartz tubes used for the reaction cannot be reused, resulting in increased preparation costs. Summary of the invention
[0005] In view of the shortcomings and deficiencies of the above prior art, the purpose of the present invention is to provide a method for preparing Sb2Se3 alloy. The method of the present invention adopts a special reaction container, and by adopting a specific heating program, the melting and mixing reaction of Sb and Se at different temperatures can be controlled, which can effectively avoid the volatilization of Se at high temperature; and by a specific method, Se is melted and then flows into the Sb liquid for reaction, thereby improving the uniformity of the components.
[0006] The purpose of the present invention is achieved through the following technical solutions:
[0007] A method for preparing a Sb2Se3 alloy comprises the following preparation steps:
[0008] (1) Sb blocks and Se blocks are placed in the first cavity and the second cavity of a quartz reactor respectively. The first cavity and the second cavity are separated by a partition and connected by a quartz pipe, and then an inert gas is introduced to exhaust the air in the quartz reactor;
[0009] (2) placing the quartz reactor in a horizontal tube furnace, and under the protection of inert gas, heating the first cavity to 660-700°C to melt Sb, and then heating the second cavity to 250-300°C to melt Se, and then heating the quartz pipe part between the first cavity and the second cavity to 250-300°C, and tilting the quartz reactor to allow the Se liquid in the second cavity to flow into the first cavity through the quartz pipe to react with the Sb liquid under heat preservation;
[0010] (3) After all the Se solution has flowed into the first cavity, the tubular furnace is erected, the furnace body is rotated and swung to continue the heat preservation reaction for homogenization treatment, and then the heating is turned off and the furnace is cooled to room temperature to obtain Sb2Se3 alloy.
[0011] Furthermore, the mass ratio of the Sb block and the Se block added in step (1) is Sb:Se=50.69:49.35-49.40. According to the chemical molecular formula Sb2Se3, the mass ratio is converted into a slightly excessive amount of Se.
[0012] Furthermore, the inert gas in step (1) is nitrogen, the gas flow rate is 3 to 5 L / min, and the ventilation time is 60 to 90 min.
[0013] Furthermore, the inert gas in step (2) is nitrogen, and the flow rate of the inert gas is controlled at 1 to 2 L / min.
[0014] Furthermore, in step (2), the heating rate of the first cavity is 5-10°C / min; the heating rate of the second cavity is 1-3°C / min; and the heating rate of the quartz pipe portion between the first cavity and the second cavity is 3-5°C / min.
[0015] Furthermore, the insulation reaction time in step (2) is 120 to 150 minutes.
[0016] Furthermore, in step (3), the furnace body is rotated at an interval of 20 minutes, the swing amplitude is ±20°, and the homogenization treatment time is 120 minutes.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] (1) By adopting a specific temperature rising program to control the melting and mixing reaction of Sb and Se at different temperatures, the volatilization of Se at high temperature can be effectively avoided, the uniformity of the components and the product yield can be improved, and the occurrence of violent reactions of a large number of substances can be prevented, making the production safe.
[0019] (2) Considering the density difference between Sb and Se, the present invention first melts Sb to form Sb metal liquid, and then slowly flows the melted Se liquid into the Sb liquid to react and generate a first Sb-rich compound. As time goes by, antimony selenide is finally formed, further ensuring the uniformity of the components.
[0020] (3) The method of the present invention utilizes a specific quartz reactor, which does not require vacuum sealing and can be used repeatedly, thereby reducing costs and achieving a yield of more than 99.8%. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 Schematic diagram of the overall structure of the quartz reactor used in the embodiment of the present invention. DETAILED DESCRIPTION
[0022] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.
[0023] Example 1
[0024] A method for preparing a Sb2Se3 alloy in this embodiment includes the following preparation steps:
[0025] (1) Select Sb and Se blocks of purity 4N5 (Se blocks are about 10 mm), and according to the chemical formula Sb2Se3, use an electronic scale with an accuracy of 0.1 g to weigh Sb:Se = 50.69:49.36, with a slight excess of Se, and place them in the first and second cavities of a clean quartz reactor, respectively. The first cavity is open at the top, and the second cavity is closed but has a feed port at the top. The first cavity and the second cavity are separated by a partition and connected by a quartz pipe. The structural schematic diagram of the quartz reactor is shown in FIG. Figure 1 Then, the air in the quartz reactor was exhausted with nitrogen, the nitrogen flow rate was 3 L / min, and the ventilation time was 40 min.
[0026] (2) Place the quartz reactor of step (1) into a horizontal tube furnace (with a horizontal baffle in the tube furnace), tilt the tube furnace by 20°, wherein the first cavity end of the quartz reactor contacts the horizontal baffle of the tube furnace, cover the tail cap, continue to introduce inert gas, and after 50 minutes of ventilation, turn on the heating power supply to start heating. First, heat the first cavity of the quartz reactor to 660°C for continuous insulation at a heating rate of 10°C / min, then heat the second cavity of the quartz reactor to 300°C at a heating rate of 3°C / min for insulation, and then heat the quartz pipe part between the first cavity and the second cavity of the quartz reactor to 300°C at a heating rate of 5°C / min for insulation. During this process, the Se liquid in the second cavity flows into the first cavity through the quartz pipe to react with the Sb liquid for insulation. The overall insulation time is 150 minutes, and the Se liquid has all flowed into the first cavity.
[0027] (3) The tubular furnace was slowly erected for swing homogenization treatment. The furnace body was rotated every 20 minutes with a swing amplitude of ±20° and a holding time of 120 minutes, so that the Sb2Se3 in the first cavity reacted more fully and more evenly. After the holding time was completed, the heating power was turned off and the furnace was cooled to room temperature. The Sb2Se3 material was taken out from the first cavity and its yield was measured to be 99.85%.
[0028] Example 2
[0029] A method for preparing a Sb2Se3 alloy in this embodiment includes the following preparation steps:
[0030] (1) Select Sb and Se blocks with a purity of 5N (Se blocks are about 10 mm), and according to the chemical formula Sb2Se3, use an electronic scale with an accuracy of 0.1 g to weigh Sb:Se = 50.69:49.38, with a slight excess of Se, and place them in the first and second cavities of a clean quartz reactor, respectively. The first cavity is open at the top, and the second cavity is closed but has a feed port at the top. The first cavity and the second cavity are separated by a partition and connected by a quartz pipe. The structural schematic diagram of the quartz reactor is shown in FIG. Figure 1 Then, the air in the quartz reactor was exhausted with nitrogen, the nitrogen flow rate was 4 L / min, and the ventilation time was 50 min.
[0031] (2) Place the quartz reactor of step (1) into a horizontal tube furnace (with a horizontal baffle in the tube furnace), tilt the tube furnace by 15°, wherein the first cavity end of the quartz reactor contacts the horizontal baffle of the tube furnace, cover the tail cap, continue to introduce inert gas, and after the ventilation time is 40 minutes, turn on the heating power supply to start heating. First, heat the first cavity of the quartz reactor to 680°C for continuous insulation at a heating rate of 8°C / min, then heat the second cavity of the quartz reactor to 270°C at a heating rate of 2°C / min for insulation, and then heat the quartz pipe part between the first cavity and the second cavity of the quartz reactor to 280°C at a heating rate of 4°C / min for insulation. During this process, the Se liquid in the second cavity flows into the first cavity through the quartz pipe to react with the Sb liquid for insulation. The overall insulation time is 120 minutes, and the Se liquid has all flowed into the first cavity.
[0032] (3) The tubular furnace was slowly erected for swing homogenization treatment. The furnace body was rotated every 20 minutes with a swing amplitude of ±20° and a holding time of 120 minutes, so that the Sb2Se3 in the first cavity reacted more fully and more evenly. After the holding time was completed, the heating power was turned off and the furnace was cooled to room temperature. The Sb2Se3 material was taken out from the first cavity and its yield was measured to be 99.88%.
[0033] Example 3
[0034] A method for preparing a Sb2Se3 alloy in this embodiment includes the following preparation steps:
[0035] (1) Select Sb and Se blocks with a purity of 5N (Se blocks are about 10 mm), and according to the chemical formula Sb2Se3, use an electronic scale with an accuracy of 0.1 g to weigh Sb:Se = 50.69:49.40, with a slight excess of Se, and place them in the first and second cavities of a clean quartz reactor, respectively. The first cavity is open at the top, and the second cavity is closed but has a feed port at the top. The first cavity and the second cavity are separated by a partition and connected by a quartz pipe. The structural schematic diagram of the quartz reactor is shown in FIG. Figure 1 Then, the air in the quartz reactor was exhausted with nitrogen, the nitrogen flow rate was 3 L / min, and the ventilation time was 60 min.
[0036] (2) Place the quartz reactor of step (1) into a horizontal tube furnace (with a horizontal baffle in the tube furnace), tilt the tube furnace by 20°, wherein the first cavity end of the quartz reactor contacts the horizontal baffle of the tube furnace, cover the tail cap, continue to introduce inert gas, and after the ventilation time is 40 minutes, turn on the heating power supply to start heating. First, heat the first cavity of the quartz reactor to 660°C for continuous insulation at a heating rate of 5°C / min, then heat the second cavity of the quartz reactor to 250°C at a heating rate of 1°C / min for insulation, and then heat the quartz pipe part between the first cavity and the second cavity of the quartz reactor to 260°C at a heating rate of 3°C / min for insulation. During this process, the Se liquid in the second cavity flows into the first cavity through the quartz pipe to react with the Sb liquid for insulation. The overall insulation time is 120 minutes, and the Se liquid has all flowed into the first cavity.
[0037] (3) The tubular furnace was slowly erected for swing homogenization treatment. The furnace body was rotated every 20 minutes with a swing amplitude of ±20° and a holding time of 120 minutes, so that the Sb2Se3 in the first cavity reacted more fully and more evenly. After the holding time was completed, the heating power was turned off and the furnace was cooled to room temperature. The Sb2Se3 material was taken out from the first cavity and its yield was measured to be 99.87%.
[0038] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.
Claims
1. A method for preparing a Sb2Se3 alloy, characterized in that: The method comprises the following preparation steps: (1) The Sb block and the Se block are placed in the first cavity and the second cavity of the quartz reactor respectively. The first cavity and the second cavity are separated by a partition and connected by a quartz pipe, and then an inert gas is introduced to exhaust the air in the quartz reactor; (2) Place the quartz reactor in a horizontal tube furnace. Under the protection of inert gas, heat the first cavity to 660-700°C to melt Sb, then heat the second cavity to 250-300°C to melt Se, and then heat the quartz pipe between the first cavity and the second cavity to 250-300°C. Tilt the quartz reactor so that the Se liquid in the second cavity flows into the first cavity through the quartz pipe to react with the Sb liquid at a heat preservation temperature. (3) After all the Se solution flows into the first cavity, the tubular furnace is erected, the furnace body is rotated and swung to continue the heat preservation reaction for homogenization treatment, and then the heating is turned off and the furnace is cooled to room temperature to obtain Sb2Se3 alloy; The mass ratio of the Sb block and the Se block added in step (1) is Sb:Se=50.69:49.35~49.40; In step (2), the heating rate of the first cavity is 5-10°C / min; the heating rate of the second cavity is 1-3°C / min; and the heating rate of the quartz pipe portion between the first cavity and the second cavity is 3-5°C / min.
2. The method for preparing a Sb2Se3 alloy according to claim 1, characterized in that: The inert gas in step (1) is nitrogen, the gas flow rate is 3-5 L / min, and the ventilation time is 60-90 min.
3. The method for preparing a Sb2Se3 alloy according to claim 1, characterized in that: The inert gas in step (2) is nitrogen, and the flow rate of the inert gas is controlled at 1-2 L / min.
4. The method for preparing a Sb2Se3 alloy according to claim 1, characterized in that: The time of the heat preservation reaction in step (2) is 120-150 minutes.
5. The method for preparing a Sb2Se3 alloy according to claim 1, characterized in that: In step (3), the furnace body is rotated at an interval of 20 minutes, the swing amplitude is ±20°, and the homogenization treatment time is 120 minutes.