Au-loaded Cu7Te4 nanowires, their preparation methods and applications
By preparing Au-supported Cu7Te4 nanowires, the problem of low efficiency of existing photocatalysts in catalyzing the reduction of carbon dioxide under infrared light was solved, achieving a highly efficient and selective conversion of carbon dioxide into carbon monoxide.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGNAN UNIV
- Filing Date
- 2024-04-22
- Publication Date
- 2026-07-31
AI Technical Summary
Existing photocatalysts are difficult to efficiently catalyze the reduction of carbon dioxide to carbon monoxide under infrared light, and their efficiency is low at room temperature and pressure, making it impossible to effectively utilize the energy of infrared light.
Au-supported Cu7Te4 nanowires were used. Au was loaded onto the surface of Cu7Te4 nanowires through a preparation method, and infrared light was used to photocatalytically reduce carbon dioxide in the air to carbon monoxide.
At room temperature and pressure, Au-supported Cu7Te4 nanowires achieved highly efficient catalytic reduction of carbon dioxide to carbon monoxide with a yield of 2.6 μmol g⁻¹h⁻¹ under infrared light, with 100% selectivity, which is 4.2 times more efficient than unsupported Cu7Te4 nanowires.
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Figure CN118454702B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an Au-supported Cu7Te4 nanowire, its preparation method, and its application, belonging to the fields of material preparation and photocatalysis. Background Technology
[0002] Carbon monoxide (CO) is a key element in a range of chemical reactions, including water conversion, Fischer-Tropsch synthesis, methanol synthesis, blast furnace steelmaking, and the Koch reaction. Besides its use as a feedstock in the chemical industry, carbon monoxide can also be used directly in various applications, such as food packaging and clinical settings. The versatility of carbon monoxide demonstrates its multifunctionality, extending beyond its role as a chemical precursor. In industry, CO is typically produced through processes such as steam reforming, coal gasification, or partial oxidation reactions. These methods usually require high temperatures and pressures, consuming significant amounts of energy.
[0003] Solar energy is pollution-free and inexhaustible, and in recent years, photocatalysis has been considered a potential "green chemistry" method for preparing chemical materials. Although many photocatalysts have been used for the photoreduction of carbon dioxide to CO, most photocatalysts typically use ultraviolet or visible light. Infrared (IR) light accounts for about 50% of solar radiation, but its application in reducing carbon dioxide remains extremely limited. This is mainly because most semiconductor photocatalysts have narrow band gaps, resulting in unfavorable conduction band (CB) positions, making the energy levels unsuitable for CO2 reduction reactions. Therefore, efforts are still needed to find highly efficient catalysts with suitable valence band positions that can perform CO2 reduction under infrared light, especially the reduction of atmospheric CO2 to CO.
[0004] Metallic conductors possess a wide range of light absorption potential, including the infrared region, due to their small band gaps. Within conductors, partially occupied energy bands facilitate continuous transitions, enabling the acquisition of broader band positions. This satisfies the theoretical mechanism of CO2 reduction to CO while ensuring IR light absorption. However, due to high carrier density, conductors frequently experience charge recombination, limiting their ability to provide a large number of electrons and holes to participate in photocatalytic redox reactions.
[0005] In conclusion, it is of great significance to develop a photocatalyst that can efficiently catalyze the reduction of CO2 into CO under infrared light conditions. Summary of the Invention
[0006] To address the aforementioned problems, the present invention aims to provide a simple new method for preparing Au-supported Cu7Te4 nanowires; based on this method, the prepared material is used to efficiently catalytically reduce atmospheric carbon dioxide to CO under infrared light conditions at room temperature and pressure.
[0007] To achieve the above objectives, the present invention first provides a method for preparing Au-supported Cu7Te4 nanowires, comprising the following steps:
[0008] (1) Preparation of tellurium nanowires: Polyvinylpyrrolidone was dissolved in double-distilled water, stirred evenly, and sodium tellurite and ammonia were added in sequence, followed by hydrazine hydrate. After mixing evenly, the reaction solution was placed in a sealed container for reaction. After the reaction was completed, it was cooled to room temperature, mixed evenly with 3 times the volume of acetone, centrifuged, and then washed with water to obtain tellurium nanowires.
[0009] (2) Preparation of Cu7Te4 nanowires: The tellurium nanowires prepared in step (1) were dispersed in ethylene glycol. After mixing evenly, copper salt and ascorbic acid were added to the tellurium nanowire dispersion. After reacting for two hours, acetone was slowly added to the mixed solution. The mixture was shaken continuously to extract the solid product. The solid was obtained by centrifugation. The solid was washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires.
[0010] (3) Preparation of Au-loaded Cu7Te4 nanowires: The Cu7Te4 nanowires obtained in step (2) were uniformly dispersed in distilled water and stirred until uniform to obtain Cu7Te4 nanowire dispersion. The Au source solution was slowly added dropwise to the Cu7Te4 nanowire dispersion. After reacting for 3 to 6 minutes, the mixture was centrifuged and washed three times with deionized water. The Au-loaded Cu7Te4 nanowires were obtained by centrifugation.
[0011] In one embodiment of the present invention, in step (1), the mass-to-volume ratio of polyvinylpyrrolidone to double-distilled water is 1 g:(30-50) mL.
[0012] In one embodiment of the present invention, in step (1), the mass ratio of sodium tellurite to polyvinylpyrrolidone added is (0.09-0.1):1.
[0013] In one embodiment of the present invention, in step (1), the mass-to-volume ratio of sodium tellurite to ammonia is 0.02 to 0.04 g / mL, and the mass-to-volume ratio of sodium tellurite to hydrazine hydrate is 0.04 to 0.08 g / mL.
[0014] In one embodiment of the present invention, in step (1), the reaction temperature is 170-180°C and the reaction time is 3-3.5 h.
[0015] In one embodiment of the present invention, in step (2), the volume ratio of the tellurium nanowires to ethylene glycol is 1:(7-8).
[0016] In one embodiment of the present invention, in step (2), the mass-to-volume ratio of the copper salt to the tellurium nanowire dispersion is 1.86 to 2.48 mg / mL, and the copper salt includes at least one of copper nitrate, copper sulfate, and copper chloride.
[0017] In one embodiment of the present invention, in step (2), the volume ratio of the ascorbic acid to the tellurium nanowire dispersion is 7.98 to 10.64 mg / mL, and the concentration of the ascorbic acid is 1.5 to 2 M.
[0018] In one embodiment of the present invention, in step (2), the amount of acetone added is 1.5 to 2 times the volume of the mixed solution.
[0019] In one embodiment of the present invention, in step (3), the concentration of the Cu7Te4 nanowire dispersion is 0.001M-0.01M.
[0020] In one embodiment of the present invention, in step (3), the volume ratio of the Au source solution to the Cu7Te4 nanowire dispersion is 1:(25-50), the Au source is tetrachloroauric acid and / or sodium chloroaurate, and the concentration of the Au source solution is 0.01-0.05M.
[0021] The present invention also provides Au-supported Cu7Te4 nanowires prepared according to the above preparation method.
[0022] The present invention also provides an application of the above-mentioned Au-supported Cu7Te4 nanowires in the field of photocatalysis.
[0023] In one embodiment of the invention, the application includes photocatalytic reduction of carbon dioxide.
[0024] In one embodiment of the present invention, the photocatalytic reduction of carbon dioxide reaction process is as follows: Au-supported Cu7Te4 is uniformly dispersed on a glass slide and placed in a sealed glass apparatus. Water is injected into the container, CO2 is introduced at an air concentration, and then a vacuum is drawn to remove the air from the sealed glass apparatus. Infrared light is used as the light energy source for the reaction, and the reaction is carried out for 0.5 to 2 hours to obtain CO.
[0025] The CO2 concentration in this invention refers to a CO2 concentration close to the concentration of CO2 in the air, which is approximately 0.03%.
[0026] In one embodiment of the present invention, the amount of Au-loaded Cu7Te4 added is 10 mg, and the volume of injected water is 2 mL.
[0027] The beneficial effects of this invention are:
[0028] 1. This preparation method is simple to operate, and the Au-supported Cu7Te4 nanowires prepared can reduce atmospheric carbon dioxide to CO under infrared light conditions, which is environmentally friendly and sustainable.
[0029] 2. The preparation method of Au-supported Cu7Te4 nanowires is simple. By using synthesized tellurium nanowires, reacting them with copper salts and ascorbic acid, separating the reaction products, reacting them with a gold source solution, and then washing them with water, Au-supported Cu7Te4 nanowires can be prepared.
[0030] 3. The Au-supported Cu7Te4 nanowires prepared by the method of this invention can be used for photocatalytic reduction of carbon dioxide under infrared light conditions. The yield of CO2 to CO from ambient air concentration can reach 2.6 μmol g under ambient temperature and pressure. -1 h -1 It is 4.2 times that of unloaded Cu7Te4 nanowires, and the selectivity is 100%. Attached Figure Description
[0031] Figure 1 The images show the XRD diffraction patterns of Au-loaded Cu7Te4 nanowires and unloaded Cu7Te4 nanowires prepared in Example 1 and Comparative Example 1, where (a) is the XRD pattern of Au-loaded Cu7Te4 nanowires and (b) is the XRD pattern of unloaded Cu7Te4 nanowires.
[0032] Figure 2 The images show transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of Au-loaded Cu7Te4 nanowires and unloaded Cu7Te4 nanowires prepared in Example 1 and Comparative Example 1, respectively. (a) and (b) are TEM and HRTEM images of unloaded Cu7Te4 nanowires, respectively, and (c) and (d) are TEM and HRTEM images of Au-loaded Cu7Te4 nanowires, respectively.
[0033] Figure 3 The images show the X-ray photoelectron spectroscopy (XPS) Au 4f orbital spectra of Au-loaded Cu7Te4 nanowires and unloaded Cu7Te4 nanowires prepared in Example 1 and Comparative Example 1, where (a) is the XPS spectrum of the unloaded Cu7Te4 nanowire and (b) is the XPS spectrum of the Au-loaded Cu7Te4 nanowire.
[0034] Figure 4 The graph shows the carbon monoxide yield obtained by infrared photocatalytic reduction of air-concentrated carbon dioxide in Examples 2 and Comparative Example 5 using Au-supported Cu7Te4 nanowires (black) and unsupported Cu7Te4 nanowires (gray).
[0035] Figure 5 Transmission electron microscope (TEM) image of Cu7Te4 nanowires prepared for Comparative Example 2.
[0036] Figure 6 Transmission electron microscope (TEM) image of Cu7Te4 nanowires prepared for Comparative Example 3.
[0037] Figure 7 Transmission electron microscope (TEM) image of Cu7Te4 nanowires prepared for Comparative Example 4. Detailed Implementation
[0038] Example 1
[0039] 1 g of PVP was placed in a 50 mL Teflon-lined container and dissolved in 33 mL of double-distilled water under magnetic stirring at 600 rpm to form a homogeneous solution at room temperature. 0.0922 g of sodium tellurite (Na₂TeO₃, 0.5 mmol) was added to this solution and dissolved. Then, 3.33 mL of ammonia water and 1.67 mL of hydrazine hydrate were added to the mixture (total reaction volume 40 mL). The container was sealed and the reaction was carried out at 180 °C for 3 hours. The mixture was then rapidly cooled to room temperature with cold tap water. At room temperature, the nanowires were mixed thoroughly with three times their volume of acetone, centrifuged, and then washed with water to obtain the tellurium nanowires.
[0040] 50 mL of tellurium nanowires were dissolved in 25 mL of ethylene glycol and transferred to a beaker, where the mixture was stirred at room temperature. Then, 0.1860 g (0.2 mmol) of Cu(NO3)2·2.5H2O and 2.4 mL of 1.89 M ascorbic acid were added to the dispersed tellurium nanowires, and the reaction was allowed to proceed for two hours. 150 mL of acetone was slowly added while continuously shaking to extract the solid product, which was then centrifuged to obtain the solid. The solid was washed twice with ethanol and then extracted again with 150 mL of acetone, centrifuged to obtain the solid product. The solid was washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires.
[0041] Cu7Te4 nanowires were uniformly dispersed in 30 mL of distilled water, transferred to a beaker and magnetically stirred at room temperature. 80 μL of 0.1 M tetrachloroauric acid solution was taken and diluted to 8 mL with deionized water. The diluted tetrachloroauric acid solution was slowly and uniformly added to the Cu7Te4 nanowire dispersion. After reacting for 5 min, the mixture was centrifuged and washed three times with deionized water. Au-loaded Cu7Te4 nanowires were obtained by centrifugation.
[0042] The structure of the compound prepared in Example 1 was identified, and the results are shown in the figure. Figures 1-3 , Figure 1 (a) is the XRD diffraction pattern of Au-supported Cu7Te4 nanowires prepared in Example 1; Figure 2 (c) and (d) are transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the Au-supported Cu7Te4 nanowires prepared in Example 1, respectively. Figure 3 X-ray photoelectron spectroscopy (XPS) of Au-supported Cu7Te4 nanowires prepared in Example 1. Figure 1 (a) The figure shows diffraction peaks at 24.7, 27.7, 43.4, and 45.4, which belong to the (002), (102), (220), and (302) planes of Cu7Te4 (JCPDS card number 18-0456), respectively, proving that the nanowires in Example 1 are Cu7Te4 nanowires; and from Figure 1 (a) The figure also shows a diffraction peak at 38.2° belonging to the (111) crystal plane of Au (JCPDS card number 04-0784), proving that Au was successfully loaded. From Figure 2 Black Au particles are clearly visible in (c), and from Figure 2 (d) shows lattice fringes belonging to Cu7Te4 and Au, indicating that Au was successfully loaded. Figure 3 The diffraction peaks of Au 4f are clearly visible, indicating that Au has been successfully loaded onto the substrate.
[0043] Comparative Example 1
[0044] 1 g of PVP was placed in a 50 mL Teflon-lined container and dissolved in 33 mL of double-distilled water under magnetic stirring at 600 rpm to form a homogeneous solution at room temperature. 0.0922 g of sodium tellurite (Na₂TeO₃, 0.5 mmol) was added to this solution and dissolved. Then, 3.33 mL of ammonia water and 1.67 mL of hydrazine hydrate were added to the mixture (total reaction volume 40 mL). The container was sealed and the reaction was carried out at 180 °C for 3 hours. The mixture was then rapidly cooled to room temperature with cold tap water. At room temperature, the nanowires were mixed thoroughly with three times their volume of acetone, centrifuged, and then washed with water to obtain tellurium nanowires.
[0045] Tellurium nanowires were dissolved in 25 mL of ethylene glycol and transferred to a beaker, where the mixture was stirred at room temperature. Then, 0.1860 g (0.2 mmol) of Cu(NO3)2·2.5H2O and 2.4 mL of 1.89 M ascorbic acid were added to the dispersed tellurium nanowires, and the reaction was allowed to proceed for two hours. 150 mL of acetone was slowly added while continuously shaking to extract the solid product, which was then centrifuged to obtain the solid. The solid product was then washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires.
[0046] The morphology and structure of the compound prepared in Comparative Example 1 were identified, and the results are shown in the figure. Figures 1-3 , Figure 1 (b) is the XRD diffraction pattern of the original Cu7Te4 nanowires prepared in Comparative Example 1. Figure 2 (a) and (b) are transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the original Cu7Te4 nanowires prepared in Comparative Example 1. (Comparison) Figure 1 (a), Figure 1 (b) No diffraction peak at 38.2 was observed, and only Cu7Te4 nanowires were obtained in Comparative Example 1.
[0047] Comparative Example 2
[0048] 1 g of PVP was placed in a 50 mL Teflon-lined container and dissolved in 33 mL of double-distilled water under magnetic stirring at 600 rpm to form a homogeneous solution at room temperature. 0.0922 g of sodium tellurite (Na₂TeO₃, 0.5 mmol) was added to this solution and dissolved. Then, 3.33 mL of ammonia water and 1.67 mL of hydrazine hydrate were added to the mixed solution (total reaction volume 40 mL). The container was sealed and placed in an autoclave. After reacting at 180 °C for 3 hours, the mixture was rapidly cooled to room temperature with cold tap water. Three volumes of acetone were then added to the final solution to precipitate the product. The precipitate was then centrifuged to obtain tellurium nanowires.
[0049] Tellurium nanowires were dissolved in 25 mL of ethylene glycol and transferred to a beaker, where the mixture was stirred at room temperature. Then, 0.1860 g (0.2 mmol) of Cu(NO3)2·2.5H2O and 2.4 mL of 1.89 M ascorbic acid were added to the dispersed tellurium nanowires, and the reaction was allowed to proceed for two hours. 150 mL of acetone was slowly added while continuously shaking to extract the solid product, which was then centrifuged to obtain the solid. The solid product was then washed twice with deionized water and centrifuged to obtain Cu7Te nanowires.
[0050] Cu7Te4 nanowires were uniformly dispersed in 30 mL of ethanol, transferred to a beaker and magnetically stirred at room temperature. 80 μL of 0.1 M tetrachloroauric acid solution was taken and diluted with ethanol to 8 mL. The diluted tetrachloroauric acid solution was slowly and uniformly added to the Cu7Te4 nanowire dispersion. After reacting for 5 min, the mixture was centrifuged and washed three times with deionized water to obtain the product.
[0051] Figure 5 The image shows a transmission electron microscope (TEM) image of the Cu7Te4 nanowires prepared for Comparative Example 2. The TEM image shows no Au particles of about 10 nm in size, and the nanowires are beaded, proving that the product obtained in Comparative Example 2 is not Au-supported Cu7Te4 nanowires.
[0052] Comparative Example 3
[0053] 1 g of PVP was placed in a 50 mL Teflon-lined container and dissolved in 33 mL of double-distilled water under magnetic stirring at 600 rpm to form a homogeneous solution at room temperature. Then, 0.0922 g of sodium tellurite (Na₂TeO₂) was added to this solution. 3， Dissolve 0.5 mmol of hydrazine in water, then add 3.33 mL of ammonia water to the mixed solution, followed by 1.67 mL of hydrazine hydrate (total reaction solution volume 40 mL). Seal the container and place it in an autoclave. React at 180 °C for 3 hours, then rapidly cool to room temperature with cold tap water. Afterward, add 3 times the volume of acetone to the final solution to precipitate the product. Centrifuge to obtain tellurium nanowires.
[0054] The nanowires were dissolved in 25 mL of ethylene glycol and transferred to a beaker, where they were stirred at room temperature. Then, 0.1860 g (0.2 mmol) of Cu(NO3)2·2.5H2O and 2.4 mL of 1.89 M ascorbic acid were added to the dispersed tellurium nanowires, and the reaction was allowed to proceed for two hours. 150 mL of acetone was slowly added while continuously shaking to extract the solid product, which was then centrifuged to obtain the solid. The solid product was then washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires.
[0055] Cu7Te4 nanowires were uniformly dispersed in 30 mL of deionized water, transferred to a beaker and magnetically stirred at 80 °C. 80 μL of 0.1 M tetrachloroauric acid solution was taken and diluted to 8 mL with deionized water. The diluted tetrachloroauric acid solution was slowly and uniformly added to the Cu7Te4 nanowire dispersion. After reacting for 5 min, the mixture was centrifuged and washed three times with deionized water to obtain the product.
[0056] Figure 6 The image shows a transmission electron microscope (TEM) image of the Cu7Te4 nanowires prepared for Comparative Example 3. The TEM image shows that the Cu7Te4 nanowires have matured and there are no Au particles of about 10 nm, proving that the product obtained is not Au-supported Cu7Te4 nanowires.
[0057] Comparative Example 4
[0058] 1 g of PVP was placed in a 50 mL Teflon-lined container and dissolved in 33 mL of double-distilled water under magnetic stirring at 600 rpm to form a homogeneous solution at room temperature. 0.0922 g of sodium tellurite (Na₂TeO₃, 0.5 mmol) was added to this solution and dissolved. Then, 3.33 mL of ammonia water and 1.67 mL of hydrazine hydrate were added to the mixed solution (total reaction volume 40 mL). The container was sealed and placed in an autoclave. After reacting at 180 °C for 3 hours, the mixture was rapidly cooled to room temperature with cold tap water. Three volumes of acetone were then added to the final solution to precipitate the product. The precipitate was then centrifuged to obtain tellurium nanowires.
[0059] Tellurium nanowires were dissolved in 25 mL of ethylene glycol and transferred to a beaker, where the mixture was stirred at room temperature. Then, 0.1860 g (0.2 mmol) of Cu(NO3)2·2.5H2O and 2.4 mL of 1.89 M ascorbic acid were added to the dispersed tellurium nanowires, and the reaction was allowed to proceed for two hours. 150 mL of acetone was slowly added while continuously shaking to extract the solid product, which was then centrifuged to obtain the solid. The solid product was then washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires.
[0060] Cu7Te4 nanowires were uniformly dispersed in 30 mL of deionized water, transferred to a beaker and magnetically stirred at room temperature. 400 μL of 0.1 M tetrachloroauric acid solution was taken and diluted to 8 mL with deionized water. The diluted tetrachloroauric acid solution was slowly and uniformly added to the Cu7Te4 nanowire dispersion. After reacting for 5 min, the mixture was centrifuged and washed three times with deionized water to obtain the product.
[0061] Figure 7 The image shows a transmission electron microscope (TEM) image of Cu7Te4 nanowires prepared for Comparative Example 4. The TEM image shows that the Au particles are too large and too numerous, and have etched the Cu7Te4 nanowires, proving that the product obtained is not Au-supported Cu7Te4 nanowires.
[0062] Example 2
[0063] 10 mg of Au-loaded Cu7Te4 powder was uniformly dispersed on a glass slide and placed in a sealed glass apparatus. 2 mL of water was added to the container, followed by the introduction of CO2 at an air concentration, and then a vacuum was created. This process was repeated three times. Infrared light was used as the light source for the reaction, and CO was obtained after 2 hours of reaction. The preparation method of the Au-loaded Cu7Te4 powder was the same as in Example 1.
[0064] Comparative Example 5
[0065] The difference between Comparative Example 5 and Example 2 is that the Au-supported Cu7Te4 was replaced with unsupported Cu7Te4 powder. The preparation method of the unsupported Cu7Te4 powder is the same as that of Comparative Example 1.
[0066] Figure 4 This diagram illustrates the yield of CO produced by the catalytic reduction of air-concentrated CO2 under infrared light for Comparative Example 5 (gray) and Example 2 (black).
[0067] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.
Claims
1. A method for preparing Au-supported Cu7Te4 nanowires, characterized in that, Includes the following steps: (1) Preparation of tellurium nanowires: Polyvinylpyrrolidone was dissolved in double-distilled water, stirred evenly, and sodium tellurite and ammonia were added in sequence, followed by hydrazine hydrate. After mixing evenly, the reaction solution was placed in a sealed container for reaction. After the reaction was completed, it was cooled to room temperature, mixed evenly with 3 times the volume of acetone, centrifuged, and then washed with water to obtain tellurium nanowires. (2) Preparation of Cu7Te4 nanowires: The tellurium nanowires prepared in step (1) were dispersed in ethylene glycol. After mixing evenly, copper salt and ascorbic acid were added to the tellurium nanowire dispersion. After reacting for two hours, acetone was slowly added to the mixed solution. The mixture was shaken continuously, the solid product was extracted, and the solid was obtained by centrifugation. The solid was washed twice with deionized water and centrifuged to obtain Cu7Te4 nanowires. (3) Preparation of Au-loaded Cu7Te4 nanowires: The Cu7Te4 nanowires obtained in step (2) were uniformly dispersed in 30 mL of distilled water and stirred evenly at room temperature to obtain a Cu7Te4 nanowire dispersion. The Au source solution was slowly added dropwise to the Cu7Te4 nanowire dispersion. After reacting for 3-6 min, the mixture was centrifuged and washed three times with deionized water. The Au-loaded Cu7Te4 nanowires were obtained by centrifugation. The Au source was tetrachloroauric acid and / or sodium chloroaurate. The concentration of the Au source solution was 0.001 M and the volume of the Au source solution was 8 mL.
2. The preparation method according to claim 1, characterized in that, In step (1), the mass-to-volume ratio of polyvinylpyrrolidone to double-distilled water is 1 g:(30~50) mL, and the mass ratio of sodium tellurite to polyvinylpyrrolidone is (0.09~0.1):
1.
3. The preparation method according to claim 1, characterized in that, In step (1), the mass-to-volume ratio of sodium tellurite to ammonia is 0.02~0.04 g / mL, the mass-to-volume ratio of sodium tellurite to hydrazine hydrate is 0.04~0.08 g / mL, the reaction temperature is 170~180℃, and the reaction time is 3~3.5 h.
4. The preparation method according to claim 1, characterized in that, In step (2), 50 mL of tellurium nanowires are dissolved in 25 mL of ethylene glycol, and the amount of acetone added is 1.5 to 2 times the volume of the mixed solution.
5. The preparation method according to claim 1, characterized in that, In step (2), the mass-to-volume ratio of the copper salt to the tellurium nanowire dispersion is 1.86~2.48 mg / mL, and the copper salt includes at least one of copper nitrate, copper sulfate, and copper chloride.
6. The preparation method according to claim 4, characterized in that, In step (2), 2.4 mL of ascorbic acid is added to the already dispersed tellurium nanowires, wherein the concentration of ascorbic acid is 1.5~2M.
7. The preparation method according to claim 1, characterized in that, In step (3), the concentration of the Cu7Te4 nanowire dispersion is 0.001M-0.01M.
8. Au-loaded Cu7Te4 nanowires prepared by the preparation method according to any one of claims 1 to 7.
9. The application of the Au-supported Cu7Te4 nanowires of claim 8 in the field of photocatalysis, wherein the application includes infrared photocatalytic reduction of carbon dioxide to CO.