Recyclable porous copper / cuprous oxide filamentous catalytic material and preparation method thereof

Abstract

The invention discloses a recyclable porous copper / cuprous oxide filamentous catalytic material and also discloses a preparation method of the catalytic material, and the preparation method comprises the following steps: taking a copper wire and pre-treating the copper wire to remove surface oxides; performing zinc electrodeposition treatment on the copper wire to obtain a galvanized copper wire; carrying out solution treatment on the galvanized copper wire to obtain a porous copper precursor; then, the porous copper precursor is subjected to corrosion treatment, zinc in a plating layer is removed, and a porous copper catalyst carrier is obtained; and putting the porous copper catalyst carrier into a tubular furnace for high-temperature oxidation to obtain the Cu / Cu2O filamentous catalytic material. The catalytic material provided by the invention has the characteristics of recoverability and good catalytic performance. According to the method, cuprous oxide is generated by adopting a one-step high-temperature thermal oxidation method, and regulation and control parameters are few and easy to control in the process.

Description

Technical Field

[0001] The present invention belongs to the technical field of photoelectric hydrogen decomposition composite catalytic materials and preparation methods thereof, and specifically relates to a recyclable porous copper / cuprous oxide filamentous catalytic material. The present invention also relates to a preparation method of the catalytic material. Background Art

[0002] Cuprous oxide (Cu2O) is an important p-type semiconductor material with a narrow bandgap (approximately 2.0-2.2 eV) and broad application prospects in photocatalysis and electrocatalysis. Compared to other catalysts, Cu2O offers advantages such as strong visible light responsiveness, low cost, non-toxicity and biodegradability, wide application, high catalytic activity, and excellent electrochemical performance. However, strong photocorrosion is a major challenge in the application of Cu2O catalysts.

[0003] Constructing a heterojunction is one of the most important approaches to overcoming the photocorrosion problem of Cu2O and improving its catalytic performance. A Chinese patent, published on January 3, 2025, with publication number CN119243224A, discloses a method for preparing a reticulated Cu2O / TiO2 composite pn-type heterojunction photoelectrocatalytic material. This method uses a dual-electrode oxidation method to prepare a reticulated TiO2 nanotube array with ultraviolet light absorption properties. Using this as a substrate, Cu2O is then loaded onto the TiO2 nanotube array using electrochemical deposition, broadening the TiO2's absorption in the visible light region. The Chinese patent with publication date of September 24, 2024 and publication number of CN118681584B discloses a method for preparing a cuprous oxide-boron nitride flower heterojunction composite photocatalyst, which utilizes the catalytic interface formed by the composite of the two catalysts to regulate the multivalent Cu(I) / Cu(II) sites, thereby promoting the directional transmission and accumulation of photogenerated carriers to the Cu(I) / Cu(II) sites; the Chinese patent with publication date of December 3, 2024 and publication number of CN119056449A discloses a method for preparing a cuprous oxide-boron nitride flower heterojunction composite photocatalyst, which utilizes the catalytic interface formed by the composite of the two catalysts to regulate the multivalent Cu(I) / Cu(II) sites, thereby promoting the directional transmission and accumulation of photogenerated carriers to the Cu(I) / Cu(II) sites; A Chinese patent discloses a method for preparing hollow porous cuprous oxide @ copper micro-nanosphere catalysts. The hollow porous cuprous oxide @ copper micro-nanospheres can improve the stability of photocatalytic materials; a Chinese patent with a publication date of July 28, 2020 and publication number CN111450828B discloses a method for rapid preparation of an octahedral copper / cuprous oxide photocatalyst. A two-step liquid phase reduction method is used to obtain an octahedral copper / cuprous oxide composite material with cuprous oxide inside and copper-coated outside.

[0004] In summary, the current research work on constructing heterojunctions based on Cu2O has the following characteristics: (1) Cu2O or its based catalysts are in the form of thin film or powder materials and cannot be recycled; (2) There are many types of heterojunctions based on Cu2O, but regardless of the type, they all improve the Cu2O photocorrosion problem by promoting the separation and transmission of photogenerated carriers and inhibiting electron-hole recombination. However, there is still room for improvement in catalytic performance. (3) Cu / Cu2O heterojunctions are mostly copper-coated cuprous oxide structures, and the two-step liquid phase reduction process used is long and difficult to control. Summary of the Invention

[0005] The purpose of the present invention is to provide a recyclable porous copper / cuprous oxide filamentous catalytic material, which has the characteristics of being recyclable and having good catalytic performance.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned material, which uses a one-step high-temperature thermal oxidation method to generate cuprous oxide, with few control parameters in the process and easy control.

[0007] The technical solution adopted by the present invention is a method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material, which is specifically implemented according to the following steps: Step 1: Take a copper wire and pretreat it to remove surface oxides; Step 2, performing zinc electrodeposition treatment on the copper wire obtained in step 1 to obtain galvanized copper wire; Step 3: performing a solution treatment on the galvanized copper wire obtained in step 2 to obtain a porous copper precursor; then, performing a corrosion treatment on the porous copper precursor to remove zinc in the coating to obtain a porous copper catalyst carrier; Step 4: placing the porous copper catalyst carrier into a tubular furnace for high-temperature oxidation to obtain a Cu / Cu2O filamentous catalytic material.

[0008] The present invention is also characterized in that: The preprocessing in step 1 is as follows: Soak the copper wire in a 0.5~1 mol / L sulfuric acid solution for 5-20 minutes to remove surface oxides, then use deionized water and anhydrous ethanol to wash off the residual sulfuric acid solution, and then clean and dry it.

[0009] The solvent of the electroplating solution used in step 2 is water, which includes the following components in the following concentrations: zinc oxide 6-10 g / L, sodium hydroxide 50-120 g / L, and sodium lauryl sulfate 0.4-1 g / L.

[0010] In step 2, the plating current is 0.5~3A / dm 2 , the electroplating time is 3~15min, and the electroplating temperature is room temperature.

[0011] The solution treatment in step 3 is specifically as follows: placing the galvanized copper wire into a tube furnace and performing solution treatment in an argon atmosphere, wherein the heating rate is 5-10°C / min, the temperature is 250-350°C, and the holding time is 2-4h.

[0012] In step 3, the porous copper precursor is corroded in a sulfuric acid solution with a concentration of 0.5 to 1.5 mol / L for 12 to 48 hours to remove zinc in the coating, and then the residual corrosive solution on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0013] In step 4, high-temperature oxidation is carried out in an air atmosphere at a temperature of 950-1050° C. for 3-7 hours.

[0014] Another technical solution adopted by the present invention is a recyclable porous copper / cuprous oxide filamentous catalytic material, which is prepared by the above method. The material is based on copper wire and has a porous copper / cuprous oxide heterostructure distributed on the surface of the copper wire.

[0015] The beneficial effects of the present invention are: (1) The catalytic material of the present invention uses copper wire as a substrate, and a porous Cu / Cu2O heterostructure is distributed on its surface. Compared with powdered cuprous oxide, the material is recyclable, which solves the problem of recycling cuprous oxide after its activity decays and prolongs the service life of the material. The flexible characteristics of the filamentous structure can be arranged in a linear or spiral shape, further improving the selectivity of the material structure. (2) The method of the present invention forms a porous copper structure by performing zinc electrodeposition and dealloying treatment on the surface of the copper wire, which significantly increases the specific surface area of the material and greatly enhances its catalytic performance. By adjusting the electroplating parameters, solution time and dealloying time, the pore size and pore distribution of the porous copper can be adjusted, thereby adjusting the distribution of the Cu / Cu2O heterojunction and improving the catalytic performance. (3) The method of the present invention uses a one-step high-temperature thermal oxidation method to generate cuprous oxide, and then forms a Cu / Cu2O heterojunction. The process is simple, the formed film has high uniformity, the cost is low and it is environmentally friendly. The Schottky junction formed by Cu and Cu2O accelerates the separation of photogenerated electron-hole pairs, forming a built-in electric field, driving the photogenerated electrons to migrate from Cu2O to Cu, while the holes remain on the Cu2O surface, achieving efficient charge separation. The high conductivity of copper complements the semiconductor properties of cuprous oxide, improving the stability and corrosion resistance of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a SEM image of the galvanized copper wire prepared in Example 1 of the present invention; Figure 2 This is a SEM image of the galvanized copper wire prepared in Example 2 of the present invention; Figure 3 This is a SEM image of the galvanized copper wire prepared in Example 3 of the present invention; Figure 4 SEM images of the porous copper catalyst supports prepared in Examples 1-6 of the present invention; Figure 5 This is a SEM image of the Cu / Cu2O filamentous catalytic material prepared in Example 8 of the present invention; Figure 6 XRD patterns of Cu / Cu2O filamentous catalytic materials prepared in Examples 3, 6, 7, and 8 of the present invention; Figure 7 The LSV treatment data of the catalytic materials prepared in Comparative Example 1 and Examples 1-8 of the present invention in 0.5 mol / L NaSO4 electrolyte; Figure 8 EIS data of the catalytic materials prepared in 0.5 mol / L NaSO4 electrolyte of Comparative Example 1, Examples 1-3, and Examples 5-8 of the present invention; Figure 9 This is the Mott-Schotty curve of the catalytic materials prepared in Comparative Example 1 and Examples 1-8 of the present invention in 0.5 mol / L NaSO4 electrolyte. DETAILED DESCRIPTION

[0017] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The method for preparing the recyclable porous copper / cuprous oxide filamentous catalytic material of the present invention is specifically implemented according to the following steps: Step 1: Soak the copper wire in a 0.5-1 mol / L sulfuric acid solution for 5-20 minutes to remove surface oxides, then use deionized water and anhydrous ethanol to wash away the residual sulfuric acid solution, and then wash and dry it; Step 2: Electrodeposit zinc on the copper wire obtained in step 1 in an electroplating bath to obtain galvanized copper wire. The electroplating solution is water and contains the following components at the following concentrations: 6-10 g / L zinc oxide, 50-120 g / L sodium hydroxide, and 0.4-1 g / L sodium lauryl sulfate; the electroplating current is 0.5-3 A / dm 2 , the electroplating time is 3~15min, and the electroplating temperature is room temperature.

[0019] Compared with traditional galvanizing on copper plates, the plating solution for galvanizing copper wire in this step has significant differences in composition, concentration, temperature, current density, etc.

[0020] Step 3: Place the galvanized copper wire obtained in step 2 into a tube furnace and perform solution treatment in an argon atmosphere, wherein the heating rate is 5-10°C / min, the temperature is 250-350°C, and the holding time is 2-4 hours to obtain a porous copper precursor; then, the precursor is corroded in a sulfuric acid solution with a concentration of 0.5-1.5 mol / L for 12-48 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0021] Step 4: generate cuprous oxide by one-step high-temperature thermal oxidation: The porous copper catalyst carrier is placed in a tube furnace for high-temperature oxidation. The temperature is raised to 950-1050°C in an air atmosphere and kept warm for 3-7 hours. After being taken out, it is washed with deionized water and anhydrous ethanol and dried to obtain a Cu / Cu2O filamentous catalytic material.

[0022] The purity of the copper wire used in the embodiment of the present invention is ≥99.9%, and the reagents such as zinc oxide used are purchased from Sinopharm Chemical Reagent Co., Ltd.

[0023] Example 1: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 5 minutes, and then wash and dry it.

[0024] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0025] Step 3: The galvanized copper wire obtained in step 2 is heated to 300°C at a rate of 10°C / min in an argon atmosphere in a tube furnace and kept warm for 3 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a 1 mol / L sulfuric acid solution for 12 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0026] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 3 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0027] Example 2: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 10 minutes, and then wash and dry it.

[0028] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 15min.

[0029] Step 3: The galvanized copper wire obtained in step 2 is heated to 300° C. at a rate of 5° C. / min in an argon atmosphere in a tube furnace and kept warm for 3 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 24 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0030] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 5 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0031] Example 3: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 20 minutes, and then wash and dry it.

[0032] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 3A / dm 2 , the electroplating time is 5min.

[0033] Step 3: The galvanized copper wire obtained in step 2 is heated to 300° C. at a rate of 8° C. / min in an argon atmosphere in a tube furnace and kept warm for 3 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 24 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0034] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 5 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0035] Example 4: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 20 minutes, and then wash and dry it.

[0036] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0037] Step 3: The galvanized copper wire obtained in step 2 is heated to 300°C at a rate of 10°C / min in an argon atmosphere in a tube furnace and kept warm for 2 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a 1 mol / L sulfuric acid solution for 12 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0038] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 3 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0039] Example 5: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 15 minutes, and then wash and dry it.

[0040] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0041] Step 3: The galvanized copper wire obtained in step 2 is heated to 300°C at a rate of 10°C / min in an argon atmosphere in a tube furnace and kept warm for 3 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 24 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0042] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 7 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0043] Example 6: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 10 minutes, and then wash and dry it.

[0044] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0045] Step 3: The galvanized copper wire obtained in step 2 is heated to 300° C. at a rate of 5° C. / min in an argon atmosphere in a tube furnace and kept warm for 4 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 12 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0046] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1050° C. in an air atmosphere and keep it warm for 3 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0047] Example 7: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 10 minutes, and then wash and dry it.

[0048] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0049] Step 3: The galvanized copper wire obtained in step 2 is heated to 350°C at a rate of 10°C / min in an argon atmosphere in a tube furnace and kept warm for 4 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 48 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0050] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 5 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0051] Example 8: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 20 minutes, and then wash and dry it.

[0052] Step 2: Electrodeposit zinc on the copper wire obtained in step 1 to obtain galvanized copper wire. The contents of the components in the electroplating solution are: 8g / L zinc oxide, 120g / L sodium hydroxide, and 0.4g / L sodium lauryl sulfate; the electroplating current is 0.5A / dm 2 , the electroplating time is 5min.

[0053] Step 3: The galvanized copper wire obtained in step 2 is heated to 300°C at a rate of 10°C / min in an argon atmosphere in a tube furnace and kept warm for 3 hours to obtain a porous copper precursor; thereafter, the precursor is corroded in a sulfuric acid solution with a concentration of 1 mol / L for 24 hours to remove zinc in the coating, and then the residual corrosive liquid on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

[0054] Step 4: Place the porous copper catalyst carrier into a corundum crucible, then place it into a tubular furnace, heat it to 1000° C. in an air atmosphere and keep it warm for 7 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0055] Comparative Example 1: This comparative example is basically the same as Example 1, except that zinc electrodeposition, solution treatment, and corrosion operations are not performed, that is, steps 2 and 3 are not performed. Instead, the copper wire is directly subjected to a high-temperature thermal oxidation step to generate cuprous oxide. The specific steps of this comparative example are: Step 1: Cut a copper wire with a length of 8 cm, soak it in 1 mol / L sulfuric acid solution for 5 minutes, and then wash and dry it.

[0056] Step 2: Place the clean copper wire obtained in step 1 into a corundum crucible, then place it into a tube furnace, heat it to 1000°C in an air atmosphere and keep it warm for 3 hours. After taking it out, wash it with deionized water and anhydrous ethanol, and dry it to obtain a Cu / Cu2O filamentous catalytic material.

[0057] The performance tests of the materials prepared in the embodiments and comparative examples of the present invention were carried out, and the results are as follows: The galvanized copper wires obtained in Examples 1-3 were tested by scanning electron microscopy. Figure 1-3 As shown, it can be seen that the zinc coating is evenly and densely wrapped on the copper wire, the particles are evenly distributed, and the particle size is 0.5-1.5μm. The distribution of the zinc coating is different under different current densities. With the change of current and electroplating time, the morphology of the zinc coating changes from uniform granular to flake and then to dendritic.

[0058] The porous copper catalyst supports prepared in Examples 1-6 were tested by scanning electron microscopy. Figure 4As shown in Table 1, it can be seen that the porous copper is evenly distributed on the surface of the copper wire, and its pore size changes with the change of electroplating time and current. As can be seen from Examples 1 and 3, when the current increases, the pore size will become larger, mainly due to the change in the zinc coating structure caused by the change in current. In addition, the solid solution parameters also have an effect on the pore size of the porous copper. As can be seen from Examples 1 and 4, after the solid solution time increases, the pore size will slightly become larger. From the above, it can be seen that the pore size of the porous copper in the catalytic material of the present invention is adjustable.

[0059] Table 1 Comparison of pore diameters of porous copper prepared in Examples 1-5

[0060] The Cu / Cu2O filamentous catalytic material prepared in Example 8 was tested by scanning electron microscopy. Figure 5 As shown in the figure, it can be seen that the cuprous oxide is distributed relatively evenly and the resulting film structure is relatively dense. The dense structure can improve the chemical stability of the film, and the uniform film structure can improve the light absorption efficiency and carrier transmission efficiency, thereby improving the performance of the catalytic material.

[0061] Figure 6 The XRD patterns of the Cu / Cu2O filamentous catalytic materials prepared in Examples 3, 6, 7, and 8 show that there is a cuprous oxide peak in the XRD pattern of each example. At different oxidation temperatures and times, the amount of cuprous oxide coating formed on the surface varies. As shown in Examples 6-8, as the holding time changes during the high-temperature oxidation process, the amount of cuprous oxide film increases significantly over time. The peak values in Examples 3 and 6 are smaller, and the cuprous oxide content may be lower.

[0062] Figure 7 The LSV treatment data of the catalytic materials prepared in Comparative Example 1 and Examples 1-8 in 0.5 mol / L NaSO4 electrolyte show that when the copper wire surface is not subjected to the porous treatment (Comparative Example 1), the LSV curve value of Cu / Cu2O is only -2.7 mA. After the copper wire surface is subjected to the porous treatment, the value increases from -2.7 mA to a maximum of -11.9 mA, and the activity and catalytic performance of the material are improved.

[0063] Figure 8These are the EIS data of the catalytic materials prepared in Comparative Example 1, Examples 1-3, and Examples 5-8 in a 0.5 mol / L NaSO4 electrolyte. The charge transfer rate at the electrode-electrolyte interface is described by the radius of the circle in the EIS diagram. The smaller the radius, the faster the charge transfer. As can be seen from the figure, Comparative Example 1 did not perform a porous treatment on the copper wire surface, and it had the largest charge transfer resistance and the slowest charge transfer. After the copper wire surface was porous treated in the embodiments, the charge transfer resistance was lower than that of Comparative Example 1, especially Example 8, whose charge transfer resistance was reduced to 1 / 3 of that of Comparative Example 1. A low charge transfer resistance is more conducive to charge transfer, indicating that its hydrogen evolution performance is better.

[0064] Figure 9 The Mott-Schotty curves of the catalytic materials prepared in Comparative Example 1 and Examples 1-8 in 0.5 mol / L NaSO4 electrolyte are shown in Table 2. The parity potentials are calculated by tangent analysis. Table 2 Potentials of catalytic materials prepared in each case

[0065] Figure 9 All materials show a negative slope, which indicates that they are all p-type semiconductors. RHE =E Ag / AgCl The parity potential was calculated by adding 0.197 V and 0.0592 × pH. As shown in Table 2, it can be seen that the parity potentials of the embodiments are slightly higher than those of the comparative example 1, which indirectly reflects that the carrier recombination rate and mobility in Cu / Cu2O are significantly improved.

Claims

1. A method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material, characterized in that: Please follow the steps below to implement it: Step 1: Take a copper wire and pretreat it to remove surface oxides; Step 2, performing zinc electrodeposition treatment on the copper wire obtained in step 1 to obtain galvanized copper wire; Step 3: performing a solution treatment on the galvanized copper wire obtained in step 2 to obtain a porous copper precursor; then, performing a corrosion treatment on the porous copper precursor to remove zinc in the coating to obtain a porous copper catalyst carrier; Step 4: placing the porous copper catalyst carrier into a tubular furnace for high-temperature oxidation to obtain a Cu / Cu2O filamentous catalytic material.

2. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, characterized in that: The preprocessing in step 1 is as follows: Soak the copper wire in a 0.5~1 mol / L sulfuric acid solution for 5-20 minutes to remove surface oxides, then use deionized water and anhydrous ethanol to wash off the residual sulfuric acid solution, and then clean and dry it.

3. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, characterized in that: The solvent of the electroplating solution used in step 2 is water, which includes the following components in the following concentrations: zinc oxide 6-10 g / L, sodium hydroxide 50-120 g / L, and sodium lauryl sulfate 0.4-1 g / L.

4. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, wherein: In step 2, the plating current is 0.5~3A / dm 2 , the electroplating time is 3~15min, and the electroplating temperature is room temperature.

5. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, wherein: The solution treatment in step 3 is specifically as follows: placing the galvanized copper wire into a tube furnace and performing solution treatment in an argon atmosphere, wherein the heating rate is 5-10°C / min, the temperature is 250-350°C, and the holding time is 2-4h.

6. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, wherein: In step 3, the porous copper precursor is corroded in a sulfuric acid solution with a concentration of 0.5 to 1.5 mol / L for 12 to 48 hours to remove zinc in the coating, and then the residual corrosive solution on the surface is cleaned with anhydrous ethanol, and the porous copper catalyst carrier is obtained after drying.

7. The method for preparing a recyclable porous copper / cuprous oxide filamentous catalytic material according to claim 1, wherein: In step 4, high-temperature oxidation is carried out in an air atmosphere at a temperature of 950-1050° C. for 3-7 hours.

8. A recyclable porous copper / cuprous oxide filament catalytic material, characterized in that: The invention is prepared by the method described in any one of claims 1 to 7, and uses copper wire as a substrate, with a porous copper / cuprous oxide heterostructure distributed on the surface of the copper wire.

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