Cu-In2O3 nanoparticle catalyst as well as preparation and application thereof

Abstract

The invention relates to the technical field of electro-catalysis, in particular to a Cu-In2O3 nanoparticle catalyst as well as a preparation method and application thereof. The method comprises the following steps: dissolving a soluble copper salt and a soluble indium salt in water together, mixing with an alkali solution, carrying out a precipitation reaction, and combining copper ions and indium ions with OH <-> ions in alkali in the precipitation reaction process to generate copper hydroxide and indium hydroxide so as to obtain a precipitate; freeze-drying the precipitate to obtain a precursor; and calcining the precursor in a mixed atmosphere of hydrogen and inert gas to obtain the Cu-In2O3 nanoparticle catalyst. The Cu-In2O3 nanoparticle catalyst disclosed by the invention not only has excellent catalytic activity and high selectivity to formic acid, but also has good stability and reusability. When the Cu-In2O3 nano-particle catalyst is applied to the electrocatalytic carbon dioxide reduction reaction, the energy consumption can be effectively reduced, and the production efficiency and the product quality of formic acid can be improved.

Description

Technical Field

[0001] The present invention relates to the field of electrocatalysis technology, and in particular to a Cu-In 2 O 3 Nanoparticle catalyst and its preparation method and application. Background Art

[0002] As a technology for converting carbon dioxide into useful chemicals, carbon dioxide electrocatalysis technology has shown great application potential. With the continuous efforts of scientific researchers in the design of new electrocatalysts, the construction of reaction systems and the exploration of reaction mechanisms, the research and development of electrocatalysts has become a key factor in promoting the large-scale commercial application of electrocatalysis technology.

[0003] As a basic organic chemical raw material, formic acid is widely used in pesticides, leather, dyes, medicine and rubber industries. However, the traditional formic acid production process usually has the problem of high energy consumption, which not only increases production costs, but also limits the improvement of formic acid production efficiency and product quality.

[0004] In the field of electrocatalytic carbon dioxide reduction, copper-based catalysts and indium oxide catalysts have each demonstrated unique performance and advantages. Copper-based catalysts have a wide range of catalytic activity and can produce a variety of products including formic acid. However, its selectivity for the production of formic acid in the electrocatalytic carbon dioxide reduction is affected by many factors, such as the composition, structure, surface morphology and reaction conditions of the catalyst. In contrast, although indium oxide catalysts show high selectivity for formic acid in the electrocatalytic carbon dioxide reduction reaction, this provides broad prospects for its application in formic acid production. However, indium oxide catalysts also face multiple challenges such as high cost, complex preparation process and feasibility of large-scale application. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a Cu-In 2 O 3 Nanoparticle catalyst and its preparation method and application. The present invention dissolves soluble copper salt and soluble indium salt, then adds alkaline solution, and obtains precipitate through precipitation reaction; freeze-drying the precipitate and then calcining it to obtain Cu-In 2 O 3 Nanoparticle catalyst. The Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst not only has excellent catalytic activity and high selectivity for formic acid, but also has good stability and reusability. 2 O 3The application of nanoparticle catalysts in the electrocatalytic carbon dioxide reduction reaction can effectively reduce energy consumption, improve the production efficiency and product quality of formic acid, and provide strong support for the realization of green and sustainable formic acid production.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The first object of the present invention is to provide a Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0008] S1. Dissolve soluble copper salt and soluble indium salt in water, mix with alkaline solution, and carry out precipitation reaction. During the precipitation reaction, copper ions and indium ions react with OH in the alkali. - ions combine to form copper hydroxide and indium hydroxide to obtain a precipitate; among them, Cu 2+ 、In 3+ With OH in the base - The molar ratio is 1-3:1-3:5-9; OH - Too little will result in incomplete reaction, Cu 2+ andIn 3+ The ratio of Cu-In 2 O 3 The performance of nanoparticle catalysts will deteriorate, Cu 2+ andIn 3 + The most preferred ratio is 1:1.

[0009] S2. Freeze-drying the precipitate to obtain a precursor; during the freeze-drying process, the precipitate is dried at a low temperature, and the water directly sublimates from the solid state to the gas state, thus avoiding the appearance of a liquid phase and being able to well maintain the original structure and properties of the precipitate.

[0010] S3, in a mixed atmosphere of hydrogen and inert gas, the precursor is calcined. During the calcination process, copper hydroxide is reduced to form copper; indium hydroxide is dehydrated to form indium trioxide to obtain Cu-In 2 O 3 Nanoparticle catalysts.

[0011] Preferably, the calcination conditions are: firstly increase the temperature to 350°C to 650°C at 5°C / min to 10°C / min, calcine for 1h to 3h, and then cool down to 20°C to 30°C at 5°C / min to 10°C / min.

[0012] Preferably, freeze-drying is performed to constant weight.

[0013] Preferably, the freeze-drying conditions are: at -40 to -50°C for 12 to 19 hours.

[0014] Preferably, the precipitation reaction is carried out under the following conditions: stirring at room temperature for 10 to 20 minutes.

[0015] Preferably, in the mixed atmosphere of hydrogen and inert gas, the volume fraction of hydrogen in the mixed atmosphere is 2% to 5%; when its volume fraction is 2% to 5%, the combustion rate of the mixed atmosphere can be significantly improved, making the combustion process more rapid and efficient, while ensuring the safety of the calcination process.

[0016] Preferably, Cu-In 2 O 3 The nanoparticle catalyst was also washed and dried, and the drying conditions were: vacuum drying at 40°C to 80°C for 10h to 20h.

[0017] Preferably, the soluble copper salt is selected from hydrated copper nitrate; more preferably, copper nitrate trihydrate, copper nitrate hexahydrate or copper chloride.

[0018] Preferably, the soluble indium salt is selected from hydrated indium nitrate; more preferably, indium nitrate tetrahydrate or indium chloride.

[0019] The second object of the present invention is to provide Cu-In obtained by the above preparation method. 2 O 3 Nanoparticle catalysts.

[0020] Preferably, Cu-In 2 O 3 The diameter of the nanoparticle catalyst is 20nm to 80nm.

[0021] The third object of the present invention is to provide the above-mentioned Cu-In 2 O 3 Application of nanoparticle catalysts in the preparation of electrocatalytic carbon dioxide to formic acid catalysts.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention provides a Cu-In 2 O 3 The preparation method of the nanoparticle catalyst comprises dissolving a soluble copper salt and a soluble indium salt in water, mixing the solution with an alkali solution, and performing a precipitation reaction. During the precipitation reaction, the copper ions and the indium ions react with the OH in the alkali. - The ions combine to generate copper hydroxide and indium hydroxide to obtain a precipitate; the precipitate is freeze-dried to obtain a precursor; the precursor is calcined in a mixed atmosphere of hydrogen and inert gas, during which copper hydroxide is reduced to generate copper; indium hydroxide is dehydrated to generate indium trioxide to obtain Cu-In 2 O 3Nanoparticle catalyst. The Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst not only has excellent catalytic activity and high selectivity for formic acid, but also has good stability and reusability. 2 O 3 The application of nanoparticle catalysts in the electrocatalytic carbon dioxide reduction reaction can effectively reduce energy consumption, improve the production efficiency and product quality of formic acid, and provide strong support for the realization of green and sustainable formic acid production.

[0024] 2. Cu-In in the present invention 2 O 3 Nanoparticle catalysts have the characteristics of stable structure, high conversion efficiency and many electrochemical active sites. This is due to the uniform distribution of copper and indium trioxide and the nanometer-scale particle size. The uniform distribution ensures that the active sites are exposed to the maximum extent, thereby improving the catalytic efficiency; at the same time, it effectively prevents the occurrence of local excessive concentration or agglomeration, thereby enhancing the Cu-In 2 O 3 The nanoparticle size also gives Cu-In 2 O 3 Nanoparticle catalysts have a larger specific surface area, which provides more space for the increase of active sites and further promotes the improvement of catalytic efficiency.

[0025] In addition, the preparation method of the present invention is simple and has a short production cycle; and no precious metals need to be introduced during the preparation process, which significantly changes the Cu-In 2 O 3 The nanoparticle catalyst microstructure and performance are improved, reducing production costs.

[0026] 3. Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst has excellent electrocatalytic activity and can reduce carbon dioxide to formic acid under electrocatalytic reduction conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The Cu-In prepared in Example 1 2 O 3 SEM image of nanoparticle catalyst, where the inset is the Cu-In prepared in Example 1 2 O 3 Particle size distribution of nanoparticle catalysts.

[0028] Figure 2 The Cu-In prepared in Example 1 2 O 3XRD patterns of the nanoparticle catalysts.

[0029] Figure 3 The Cu-In prepared in Examples 1 to 5 2 O 3 Nanoparticle catalysts in CO 2 LSV plot in ambient electrolyte.

[0030] Figure 4 The Cu-In prepared in Example 1 2 O 3 Nanoparticle catalysts in CO 2 IT diagram in ambient electrolyte.

[0031] Figure 5 The Cu-In prepared in Example 1 2 O 3 EDS spectrum of nanoparticle catalyst. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in combination with the data in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that the professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, the various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods.

[0034] In the prior art, although copper-based catalysts and indium oxide catalysts have their own advantages in the field of electrocatalytic carbon dioxide reduction, it is often difficult to balance high selectivity and economic feasibility when used alone. Although copper-based catalysts have a wide range of activities, they show different selectivity for specific products (such as formic acid) and are easily restricted by various preparation and operation parameters. Although indium oxide catalysts show high selectivity for formic acid, their high cost and complex preparation process limit their widespread application.

[0035] In view of the above technical defects, the present invention provides a Cu-In 2 O 3 The preparation method of the nanoparticle catalyst comprises the following steps: dissolving a soluble copper salt and a soluble indium salt in water, mixing them with an alkali solution, and performing a precipitation reaction. During the precipitation reaction, the copper ions and the indium ions react with the OH in the alkali. -ions combine to form copper hydroxide and indium hydroxide to obtain a precipitate; among them, Cu 2+ 、In 3+ With OH in the base - The molar ratio of is 1-3:1-3:5-9; the precipitate is freeze-dried to obtain a precursor; the precursor is calcined in a mixed atmosphere of hydrogen and inert gas, during which copper hydroxide is reduced to form copper; indium hydroxide is dehydrated to form indium trioxide to obtain Cu-In 2 O 3 Nanoparticle catalysts.

[0036] The Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst not only has excellent catalytic activity and high selectivity for formic acid, but also has good stability and reusability. 2 O 3 The application of nanoparticle catalysts in the electrocatalytic carbon dioxide reduction reaction can effectively reduce energy consumption, improve the production efficiency and product quality of formic acid, and provide strong support for the realization of green and sustainable formic acid production.

[0037] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

[0038] Example 1

[0039] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0040] S1. Disperse 97 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 10 min until uniformly dispersed. Then, add 3 mL of sodium hydroxide solution and stir for 20 min to obtain a precipitate.

[0041] S2. The precipitate was placed in a refrigerator and frozen at -20°C for 2 h, and then transferred to a freeze drying oven and freeze-dried at -45°C for 14 h to obtain a precursor.

[0042] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 500°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 500°C for 2h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 60°C for 12h to obtain Cu-In 2 O 3Nanoparticle catalyst, denoted as Cu-In 2 O 3 -1; among which, H 2 The volume fraction is 5%.

[0043] Example 2

[0044] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0045] S1. Disperse 290 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 12 min until uniformly dispersed. Then, add 5 mL of sodium hydroxide solution and stir for 15 min to obtain a precipitate.

[0046] S2. The precipitate was placed in a refrigerator and frozen at -15°C for 2.5 h, and then transferred to a freeze drying oven and freeze-dried at -50°C for 16 h to obtain a precursor.

[0047] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 600°C at 10°C / min in a tube furnace with a mixed atmosphere of Ar and argon, and calcined at 600°C for 2h. After calcination, it was cooled to 25°C at 10°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 60°C for 14h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 -2; Among them, H 2 The volume fraction is 2%.

[0048] Example 3

[0049] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0050] S1. Disperse 190 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 12 min until uniformly dispersed. Then, add 5 mL of sodium hydroxide solution and stir for 15 min to obtain a precipitate.

[0051] S2. The precipitate was placed in a refrigerator and frozen at -15°C for 3 h, and then transferred to a freeze drying oven and freeze-dried at -40°C for 16 h to obtain a precursor.

[0052] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2The mixture was heated to 450°C at a rate of 10°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 450°C for 3 h. After calcination, it was cooled to 25°C at a rate of 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven and dried at 80°C for 10 h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 -3; Among them, H 2 The volume fraction is 2%.

[0053] Example 4

[0054] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0055] S1. Disperse 97 mg of copper nitrate and 240 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 10 min until uniformly dispersed. Then, add 3 mL of sodium hydroxide solution and stir for 13 min to obtain a precipitate.

[0056] S2. The precipitate was placed in a refrigerator and frozen at -18°C for 2 h, and then transferred to a freeze drying oven and freeze-dried at -45°C for 14 h to obtain a precursor.

[0057] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 650°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 650°C for 1.5h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 50°C for 16h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 -0.5; among which, H 2 The volume fraction is 3%.

[0058] Example 5

[0059] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0060] S1. Disperse 97 mg of copper nitrate and 360 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 15 min until uniformly dispersed. Then, add 5 mL of sodium hydroxide solution and stir for 10 min to obtain a precipitate.

[0061] S2. The precipitate was placed in a refrigerator and frozen at -20°C for 2.5 h, and then transferred to a freeze drying oven and freeze-dried at -50°C for 16 h to obtain a precursor.

[0062] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 400°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 400°C for 3 h. After calcination, it was cooled to 30°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 80°C for 10 h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 -0.3; among which, H 2 The volume fraction is 5%.

[0063] Example 6

[0064] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0065] S1. Disperse 190 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 15 min until uniformly dispersed. Then, add 2 mL of sodium hydroxide solution and stir for 13 min to obtain a precipitate.

[0066] S2. The precipitate was placed in a refrigerator and frozen at -18°C for 2.5 h, and then transferred to a freeze drying oven and freeze-dried at -45°C for 15 h to obtain a precursor.

[0067] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 450°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 450°C for 3 h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 70°C for 14 h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 ; Among them, H 2 The volume fraction is 2%.

[0068] Example 7

[0069] A Cu-In 2 O 3The method for preparing a nanoparticle catalyst comprises the following steps:

[0070] S1. Disperse 97 mg of copper nitrate and 240 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 15 min until uniformly dispersed. Then, add 5 mL of sodium hydroxide solution and stir for 15 min to obtain a precipitate.

[0071] S2. The precipitate was placed in a refrigerator and frozen at -15°C for 3 h, and then transferred to a freeze drying oven and freeze-dried at -40°C for 16 h to obtain a precursor.

[0072] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 600°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 600°C for 3 h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 50°C for 16 h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 ; Among them, H 2 The volume fraction is 4%.

[0073] Example 8

[0074] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0075] S1. Disperse 290 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 12 min until uniformly dispersed. Then, add 3 mL of sodium hydroxide solution and stir for 13 min to obtain a precipitate.

[0076] S2. The precipitate was placed in a refrigerator and frozen at -20°C for 2.5 h, and then transferred to a freeze drying oven and freeze-dried at -45°C for 15 h to obtain a precursor.

[0077] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 500°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 500°C for 2h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 50°C for 16h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3; Among them, H 2 The volume fraction is 5%.

[0078] Example 9

[0079] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0080] S1. Disperse 97 mg of copper nitrate and 240 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 12 min until uniformly dispersed. Then, add 2 mL of sodium hydroxide solution and stir for 15 min to obtain a precipitate.

[0081] S2. The precipitate was placed in a refrigerator and frozen at -18°C for 2 h, and then transferred to a freeze drying oven and freeze-dried at -50°C for 16 h to obtain a precursor.

[0082] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2 The mixture was heated to 650°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 650°C for 1.5h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 60°C for 12h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 ; Among them, H 2 The volume fraction is 3%.

[0083] Example 10

[0084] A Cu-In 2 O 3 The method for preparing a nanoparticle catalyst comprises the following steps:

[0085] S1. Disperse 290 mg of copper nitrate and 120 mg of indium nitrate uniformly in 10 mL of deionized water, and ultrasonicate for 13 min until uniformly dispersed. Then, add 1 mL of sodium hydroxide solution and stir for 10 min to obtain a precipitate.

[0086] S2. The precipitate was placed in a refrigerator and frozen at -15°C for 3 h, and then transferred to a freeze drying oven and freeze-dried at -45°C for 12 h to obtain a precursor.

[0087] S3. After placing the precursor in a porcelain boat, place the porcelain boat in a 2The mixture was heated to 600°C at 5°C / min in a tube furnace with a mixed atmosphere of argon and Ar, and calcined at 600°C for 3 h. After calcination, it was cooled to 25°C at 5°C / min, and then washed with deionized water. After washing, it was placed in a vacuum oven at 80°C for 10 h to obtain Cu-In 2 O 3 Nanoparticle catalyst, denoted as Cu-In 2 O 3 ; Among them, H 2 The volume fraction is 2%.

[0088] observe Figure 1 and Figure 5 It is concluded that the Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst has a distinct nanoparticle shape, and copper and indium trioxide are evenly distributed. Among them, the even distribution of copper and indium trioxide can maximize the exposure of active sites, thereby improving the catalytic efficiency; at the same time, it can avoid local excessive concentration or agglomeration, thereby improving the Cu-In 2 O 3 Stability of nanoparticle catalysts. Figure 1 The illustration in the figure shows that Cu-In 2 O 3 The diameter of the nanoparticle catalyst is concentrated in the range of 20nm to 80nm. 2 O 3 Nanoparticle catalysts have nanometer-scale particle sizes, which give them a larger specific surface area. A larger specific surface area provides more active sites, thereby improving catalytic efficiency.

[0089] observe Figure 2 It is concluded that the Cu-In prepared by the present invention 2 O 3 The nanoparticle catalyst contains Cu metal particles and ln 2 O 3 The crystal phase of Cu and ln 2 O 3 Successful reunion.

[0090] Examples 1 to 10 of the present invention all obtained Cu-In 2 O 3 Nanoparticle catalysts have similar performance. The following examples 1 to 5 are prepared using Cu-In 2 O 3 The performance of nanoparticle catalysts is studied as follows:

[0091] The Cu-In prepared in Examples 1 to 5 were respectively 2 O 3Nanoparticle catalysts are prepared into ink (Cu-In 2 O 3 Nanoparticle catalyst, Nafion, and deionized water were formed into an ink-like slurry under ultrasonic conditions and drop-coated on an area of ​​1 cm 2 On carbon paper, Cu-ln 2 O 3 electrodes, respectively, are denoted as Cu-ln 2 O 3 -1 electrode, Cu-ln 2 O 3 -2 electrode, Cu-ln 2 O 3 -3 electrode, Cu-ln 2 O 3 -0.5 electrode, Cu-ln 2 O 3 -0.3 electrode.

[0092] Cu-ln 2 O 3 -1 electrode, Cu-ln 2 O 3 -2 electrode, Cu-ln 2 O 3 -3 electrode, Cu-ln 2 O 3 -0.5 electrode, Cu-ln 2 O 3 -0.3 electrode as the working electrode, platinum wire as the anode, Ag / AgCl as the reference electrode, and assemble the working electrode, reference electrode and one end of the counter electrode into an H-type electrolytic cell and place it in a CO 2 Saturated 0.1 mol / L KHCO 3 The other end was electrically connected to the electrochemical workstation at a scan rate of 100 mv s -1 Electrochemical performance tests were carried out.

[0093] After the reaction is completed, the electrolyte at the anode is collected and detected by nuclear magnetic resonance spectroscopy (1HNMR) to obtain a linear scanning voltammetry curve.

[0094] observe Figure 3 It is concluded that at the same voltage, Cu-ln 2 O 3 The current density of the -1 electrode is the largest.

[0095] observe Figure 4 It is concluded that during the long electrolysis process, Cu-ln 2 O 3 -1 electrode current density did not decrease significantly, indicating that the Cu-ln2 O 3 -1 has stable catalytic performance.

[0096] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiment, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the attached claims are intended to be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the present invention.

Claims

1. A method for preparing a Cu-In2O3 nanoparticle catalyst, characterized in that: The following steps are involved: After the soluble copper salt and the soluble indium salt are dissolved in water, they are mixed with an alkaline solution and subjected to a precipitation reaction. During the precipitation reaction, the copper ions and indium ions react with the OH in the alkali. - ions combine to form copper hydroxide and indium hydroxide to obtain a precipitate; among them, Cu 2+ 、In 3+ With OH in the base - The molar ratio is 1-3:1-3:5-9; The precipitate is freeze-dried to obtain a precursor; The precursor is calcined in a mixed atmosphere of hydrogen and inert gas. During the calcination process, copper hydroxide is reduced to form copper; indium hydroxide is dehydrated to form indium trioxide, thereby obtaining a Cu-In2O3 nanoparticle catalyst.

2. The method for preparing a Cu-In2O3 nanoparticle catalyst according to claim 1, characterized in that: The conditions for the precipitation reaction are: stirring at room temperature for 10 min to 20 min.

3. The method for preparing a Cu-In2O3 nanoparticle catalyst according to claim 1, characterized in that: The calcination conditions are: calcination at 350°C to 650°C for 1h to 3h.

4. The method for preparing a Cu-In2O3 nanoparticle catalyst according to claim 1, characterized in that: In the mixed atmosphere of hydrogen and inert gas, the volume fraction of hydrogen in the mixed atmosphere is 2% to 5%.

5. The method for preparing a Cu-In2O3 nanoparticle catalyst according to claim 1, characterized in that: Freeze-dry to constant weight.

6. A Cu-In2O3 nanoparticle catalyst prepared by the preparation method of the Cu-In2O3 nanoparticle catalyst according to any one of claims 1 to 5.

7. The Cu-In2O3 nanoparticle catalyst according to claim 6, characterized in that: The diameter of the Cu-In2O3 nanoparticle catalyst is 20nm to 80nm.

8. Use of the Cu-In2O3 nanoparticle catalyst according to claim 6 in preparing a catalyst for electrocatalytic carbon dioxide production of formic acid.

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