Functionalized oxide-loaded noble metal electrocatalyst as well as preparation method and application thereof

Abstract

The invention discloses a functionalized oxide-loaded noble metal electrocatalyst and a preparation method and application thereof, the preparation method comprises the following steps: (1) adding a transition metal oxide and a silane reagent into absolute ethyl alcohol, heating and stirring, carrying out suction filtration, cleaning a solid, and drying to obtain an amino-functionalized transition metal oxide or a sulfydryl-functionalized transition metal oxide; (2) dissolving a noble metal compound in deionized water, adding a product obtained in the step (1), and carrying out ultrasonic treatment, suction filtration, solid cleaning and drying; and (3) annealing, cleaning and drying the product obtained in the step (2) in inert gas to obtain the functionalized oxide loaded noble metal electrocatalyst. According to the method, the utilization rate of precious metal is increased, the conductivity of the substrate is enhanced, and meanwhile, the bifunctional catalytic performance of transition metal oxide is utilized. The method is simple and easy to operate, and the synthesized catalyst has good catalytic activity and stability in a zinc air battery device.

Description

Technical Field

[0001] The present invention belongs to the field of catalytic technology, and in particular relates to a functionalized oxide-supported noble metal electrocatalyst and a preparation method and application thereof. Background Art

[0002] The energy structure dominated by fossil fuels has led to a series of environmental and climate problems, bringing increasingly severe challenges to human survival and development. Developing efficient energy conversion and storage technologies to increase the proportion of renewable clean energy such as hydrogen, solar energy, and wind energy in the global energy structure is one of the effective ways to meet the above challenges. Hydrogen production by water electrolysis, metal-air batteries, and fuel cells are considered to be efficient and reliable electrochemical energy conversion technologies. Oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are important half reactions involved in the above devices. However, the slow kinetics of OER and ORR make the overpotential of this type of electrochemical energy conversion device higher, resulting in problems such as low conversion efficiency. It is crucial to develop OER and ORR electrocatalysts with high activity and good stability to reduce the overpotential for this type of energy conversion technology.

[0003] Iridium dioxide and platinum carbon are representative commercial oxygen evolution catalysts and oxygen reduction catalysts, respectively. However, the scarce and expensive resources of precious metals such as iridium and platinum have seriously restricted the widespread application of electrocatalytic energy conversion technology. Transition metals have the advantages of abundant reserves and low cost. Among them, transition metal oxides have certain catalytic activity for both OER and ORR, and have good stability, but their catalytic activity is still lower than that of precious metals. Therefore, combining precious metals and transition metals is a favorable strategy to balance the activity and cost of electrocatalysts, but it has not been reported yet. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a functionalized oxide-supported noble metal electrocatalyst.

[0005] The second object of the present invention is to provide a method for preparing a functionalized oxide-supported noble metal electrocatalyst.

[0006] The third object of the present invention is to provide a functionalized oxide-supported noble metal electrocatalyst for use in oxygen evolution reaction or oxygen reduction reaction.

[0007] The technical solution of the present invention is summarized as follows:

[0008] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0009] (1) adding a transition metal oxide and a silane reagent to anhydrous ethanol, wherein the volume ratio of the silane reagent to the anhydrous ethanol is 1:(50-80), and the mass ratio of the transition metal oxide to the silane reagent is 1:(0.1-10); the silane reagent is an aminosilane reagent or a mercaptosilane reagent; heating and stirring at 60-100° C. for 12-36 hours, filtering or centrifuging, and washing the obtained solid with anhydrous ethanol and deionized water in turn, and drying to obtain an amino-functionalized transition metal oxide or a mercapto-functionalized transition metal oxide;

[0010] (2) dissolving 5-50 mg of a noble metal compound in 10-50 ml of deionized water, adding 0.05-0.5 g of the amino-functionalized transition metal oxide or the thiol-functionalized transition metal oxide obtained in step (1), ultrasonicating for 0.5-3 h, filtering or centrifuging, washing the solid with deionized water, and drying to obtain an amino-functionalized transition metal oxide or a thiol-functionalized transition metal oxide attached to a noble metal;

[0011] (3) annealing the product obtained in step (2) under the protection of an inert gas or nitrogen, taking it out, washing it with deionized water, and drying it to obtain a functionalized oxide-supported noble metal electrocatalyst.

[0012] Preferably, the transition metal oxide is cobalt tetroxide, cobaltous oxide, iron oxide, manganese dioxide, nickel oxide, copper oxide, zinc oxide, cerium oxide or tungsten trioxide.

[0013] Preferably, the aminosilane reagent is 3-aminopropyltriethoxysilane or N-aminoethyl-3-aminopropyltriethoxysilane.

[0014] Preferably, the mercaptosilane reagent is 3-mercaptopropyltriethoxysilane or mercaptopropyltrimethoxysilane.

[0015] Preferably, the noble metal compound is iridium trichloride, iridium tetrachloride, chloroiridic acid, iridium acetylacetonate, ruthenium chloride, platinum acetylacetonate, platinum chloride or chloroplatinic acid.

[0016] Preferably, the annealing in step (3) is as follows: heating to 300-450° C. at a heating rate of 3-10° C. / min, maintaining for 1-4 hours, and then cooling to room temperature.

[0017] The functionalized oxide-supported noble metal electrocatalyst prepared by the preparation method.

[0018] Application of the above-mentioned functionalized oxide-supported precious metal electrocatalyst in oxygen evolution reaction or oxygen reduction reaction.

[0019] Advantages of the present invention:

[0020] After annealing, the heteroatom N / S in the amino-functionalized transition metal oxide attached to the noble metal or the thiol-functionalized transition metal oxide attached to the noble metal plays a bridging role between the noble metal and the transition metal site, enhancing the interaction between the noble metal and the substrate, making the noble metal in a redox state that is more conducive to the reaction, and greatly improving the catalytic activity. Electrochemical tests show that when the transition metal oxide is directly loaded with noble metals, the 2 The overpotential of the catalyst is 329 mV at a current density of 10 mA / cm2, and the half-wave potential of the oxygen reduction reaction is 0.642 V. The functionalized oxide-supported noble metal electrocatalyst of the present invention has a high overpotential at 10 mA / cm2. 2 The overpotential at the current density is 254mV, and the half-wave potential of the oxygen reduction reaction is 0.682V. Compared with the two, the oxygen evolution reaction performance is improved by 75mV, and the oxygen reduction performance is improved by 40mV.

[0021] The present invention makes full use of the advantages of good catalytic activity of noble metals. Amino-functionalized transition metal oxides or thiol-functionalized transition metal oxides provide more sites for anchoring noble metals on the surface of transition metal oxides, thereby improving the utilization rate of noble metals and enhancing the conductivity of the substrate. The dual-functional catalytic performance of transition metal oxides is utilized.

[0022] The method of the invention is simple and easy to operate, and the synthesized catalyst has good catalytic activity and stability in a zinc-air battery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a scanning electron microscope image of the functionalized oxide-supported precious metal electrocatalyst Ir@N-Co3O4 obtained in Example 1.

[0024] Figure 2 These are the X-ray diffraction images of the precious metal electrocatalyst Ir@N-Co3O4 supported by the functionalized oxide obtained in Example 1 and the precious metal electrocatalyst Ir@Co3O4 directly supported by the oxide.

[0025] Figure 3 It is the N1s high-resolution X-ray photoelectron energy spectrum of the amino-functionalized transition metal oxide (amino-functionalized cobalt tetroxide NH2-Co3O4) obtained in step (1) of Example 1 and the functionalized oxide-supported precious metal electrocatalyst (Ir@N-Co3O4) obtained in step (3).

[0026] Figure 4 It is the OER polarization curve diagram of the precious metal electrocatalyst Ir@N-Co3O4 supported by the functionalized oxide obtained in Example 1 and the precious metal electrocatalyst Ir@Co3O4 directly supported by the oxide measured by linear sweep voltammetry.

[0027] Figure 5 This is a diagram of the ORR polarization curves of the precious metal electrocatalyst Ir@N-Co3O4 supported by the functionalized oxide obtained in Example 1 and the precious metal electrocatalyst Ir@Co3O4 directly supported by the oxide measured by linear sweep voltammetry.

[0028] Figure 6 The discharge curve and power density diagram of the zinc-air battery containing the precious metal electrocatalyst Ir@N-Co3O4 supported by the functionalized oxide obtained in Example 1 and the commercial Pt / C+IrO2.

[0029] Figure 7 This is a constant current charge and discharge curve of the zinc-air battery containing the precious metal electrocatalyst Ir@N-Co3O4 supported by the functionalized oxide obtained in Example 1 and the commercial Pt / C+IrO2. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the embodiments and drawings. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. 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.

[0031] The reagents and raw materials used in this example are all commercially available products.

[0032] Example 1

[0033] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0034] (1) 2 g of cobalt tetraoxide and 2 ml (1.8 g) of 3-aminopropyltriethoxysilane are added to 150 ml of anhydrous ethanol, a clean magnetic rod is placed in a flask, a condensation reflux device is installed, and the mixture is heated at 80° C. in a magnetic stirring oil bath, stirred for 24 hours, and filtered. The obtained solid is washed with anhydrous ethanol and deionized water in turn, and dried at 60° C. for 12 hours to obtain an amino-functionalized transition metal oxide (amino-functionalized cobalt tetraoxide);

[0035] (2) Dissolve 10 mg of iridium trichloride in 30 ml of deionized water, add 0.1 g of amino-functionalized cobalt tetroxide obtained in step (1), ultrasonicate for 1 hour, filter, wash the solid with deionized water, and dry at 60° C. for 12 hours to obtain amino-functionalized cobalt tetroxide with iridium attached.

[0036] (3) The product obtained in step (2) was placed in a tubular furnace under argon atmosphere, heated to 350°C at a rate of 5°C / min, maintained for 2 hours, cooled to room temperature, taken out, repeatedly cleaned with deionized water, and dried at 60°C for 12 hours to obtain a functionalized oxide-supported precious metal electrocatalyst (Ir@N-Co3O4).

[0037] SEM images of the functionalized oxide-supported noble metal electrocatalyst Ir@N-Co3O4 are shown in Figure 2. Figure 1 As shown, the randomly aggregated Ir@N-Co3O4 particles have no characteristic morphology.

[0038] Preparation of precious metal electrocatalyst Ir@Co3O4 directly supported by oxide:

[0039] Dissolve 10 mg of iridium trichloride in 30 ml of deionized water, add 0.1 g of cobalt tetraoxide, ultrasonicate for 1 hour, filter, wash the solid with deionized water, and dry at 60°C for 12 hours to obtain cobalt tetraoxide attached with iridium. Heat the obtained cobalt tetraoxide attached with iridium to 350°C at a heating rate of 5°C / min in a tube furnace under the protection of argon atmosphere, maintain for 2 hours, cool to room temperature, take out, wash repeatedly with deionized water, and dry at 60°C for 12 hours to obtain the precious metal electrocatalyst directly supported by the oxide (Ir@Co3O4)

[0040] Figure 2 These are the X-ray diffraction images of the precious metal electrocatalyst Ir@N-Co3O4 supported on functionalized oxides and the precious metal electrocatalyst Ir@Co3O4 directly supported on oxides. The doping of Ir and the introduction of amino groups still retain the crystal structure of spinel Co3O4.

[0041] Figure 3 It is the N1s high-resolution X-ray photoelectron energy spectrum of the amino-functionalized transition metal oxide (amino-functionalized cobalt tetroxide NH2-Co3O4) obtained in step (1) of Example 1 and the functionalized oxide-supported precious metal electrocatalyst (Ir@N-Co3O4) obtained in step (3).

[0042] NH2-Co3O4 contains amino N, and the N1s peak of Ir@N-Co3O4 shifts slightly to the low energy level as a whole, and Ir / Co-Nx components are formed, indicating that the loading of Ir on Co3O4 after amino functionalization treatment promotes the formation of Ir / Co-Nx sites.

[0043] Example 2

[0044] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0045] (1) adding 20 g of cobaltous oxide and 2 ml (2 g) of N-aminoethyl-3-aminopropyltriethoxysilane to 100 ml of anhydrous ethanol, placing a clean magnet in a flask, installing a condensation reflux device, heating at 60° C. in a magnetic stirring oil bath, stirring for 36 hours, filtering, washing the obtained solid with anhydrous ethanol and deionized water in turn, and drying at 60° C. for 12 hours to obtain an amino-functionalized transition metal oxide (amino-functionalized cobaltous oxide);

[0046] (2) dissolving 5 mg of chloroiridic acid in 10 ml of deionized water, adding 0.05 g of the amino-functionalized cobaltous oxide obtained in step (1), ultrasonicating for 30 min, filtering, washing the solid with deionized water, and drying at 60° C. for 12 hours to obtain amino-functionalized cobaltous oxide with iridium attached;

[0047] (3) The product obtained in step (2) was placed in a tubular furnace under nitrogen atmosphere, heated to 300° C. at a heating rate of 3° C. / min, maintained for 4 h, cooled to room temperature, taken out, repeatedly washed with deionized water, and dried at 60° C. for 12 h to obtain a functionalized oxide-supported precious metal electrocatalyst (Ir@N-CoO).

[0048] Example 3

[0049] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0050] (1) 0.2 g of tungsten trioxide and 2 ml (2 g) of N-aminoethyl-3-aminopropyltriethoxysilane were added to 160 ml of anhydrous ethanol, a clean magnet was placed in a flask, a condensation reflux device was installed, and the mixture was heated at 100° C. in a magnetic stirring oil bath, stirred for 12 hours, and centrifuged. The obtained solid was washed with anhydrous ethanol and deionized water in turn, and dried at 60° C. for 12 hours to obtain an amino-functionalized transition metal oxide (amino-functionalized tungsten trioxide);

[0051] (2) Dissolve 50 mg of iridium acetylacetonate in 50 ml of deionized water, add 0.5 g of the amino-functionalized tungsten trioxide obtained in step (1), sonicate for 3 hours, centrifuge, wash the solid with deionized water, and dry at 60° C. for 12 hours to obtain amino-functionalized tungsten trioxide attached with iridium;

[0052] (3) The product obtained in step (2) was heated to 450°C at a heating rate of 10°C / min in a tubular furnace under argon atmosphere, maintained for 1 hour, cooled to room temperature, taken out, repeatedly cleaned with deionized water, and dried at 60°C for 12 hours to obtain a functionalized oxide-supported precious metal electrocatalyst (Ir@N-WO3).

[0053] Experiments have shown that by replacing the cobalt tetroxide in Example 1 with iron oxide, manganese dioxide, nickel oxide, copper oxide, zinc oxide or cerium oxide, respectively, with the other conditions being the same as Example 1, corresponding functionalized oxide-supported precious metal electrocatalysts can be obtained.

[0054] Experiments have shown that by replacing the iridium trichloride in Example 1 with iridium tetrachloride, ruthenium chloride, platinum acetylacetonate, platinum chloride or chloroplatinic acid, respectively, with the other conditions being the same as Example 1, the corresponding functionalized oxide-supported precious metal electrocatalysts can be obtained.

[0055] Example 4

[0056] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0057] (1) 2 g of iron oxide and 2 ml (2 g) of 3-mercaptopropyltriethoxysilane are added to 150 ml of anhydrous ethanol, a clean magnetic bar is placed in a flask, a condensation reflux device is installed, and the mixture is heated at 80° C. in a magnetic stirring oil bath, stirred for 24 hours, and filtered. The obtained solid is washed with anhydrous ethanol and deionized water in turn, and dried at 60° C. for 12 hours to obtain a thiol-functionalized transition metal oxide (thiol-functionalized iron oxide);

[0058] (2) dissolving 10 mg of chloroplatinic acid in 30 ml of deionized water, adding 0.1 g of the thiol-functionalized iron oxide obtained in step (1), ultrasonicating for 1 hour, filtering, washing the solid with deionized water, and drying at 60° C. for 12 hours to obtain the thiol-functionalized iron oxide attached with platinum;

[0059] (3) The product obtained in step (2) was heated to 350°C at a rate of 5°C / min in a tube furnace under argon atmosphere protection, maintained for 2 hours, cooled to room temperature, taken out, repeatedly washed with deionized water, and dried at 60°C for 12 hours to obtain a functionalized oxide-supported precious metal electrocatalyst (Pt@S-Fe2O3)

[0060] Example 5

[0061] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0062] (1) 20 g of nickel oxide and 2 ml (2 g) of 3-mercaptopropyltriethoxysilane are added to 100 ml of anhydrous ethanol, a clean magnet is placed in a flask, a condensation reflux device is installed, and the mixture is heated at 60° C. in a magnetic stirring oil bath, stirred for 36 hours, and filtered. The obtained solid is washed with anhydrous ethanol and deionized water in turn, and dried at 60° C. for 12 hours to obtain a thiol-functionalized transition metal oxide (thiol-functionalized nickel oxide);

[0063] (2) dissolving 5 mg of ruthenium chloride in 10 ml of deionized water, adding 0.05 g of the thiol-functionalized nickel oxide obtained in step (1), ultrasonicating for 30 min, filtering, washing the solid with deionized water, and drying at 60° C. for 12 hours to obtain thiol-functionalized nickel oxide attached with ruthenium;

[0064] (3) The product obtained in step (2) was placed in a tubular furnace under nitrogen atmosphere, heated to 300° C. at a heating rate of 3° C. / min, maintained for 4 h, cooled to room temperature, taken out, repeatedly washed with deionized water, and dried at 60° C. for 12 h to obtain a functionalized oxide-supported precious metal electrocatalyst (Ru@S-NiO).

[0065] Example 6

[0066] The method for preparing a functionalized oxide-supported noble metal electrocatalyst comprises the following steps:

[0067] (1) 0.2 g of cerium oxide and 2 ml (2 g) of mercaptopropyltrimethoxysilane are added to 160 ml of anhydrous ethanol, a clean magnet is placed in a flask, a condensation reflux device is installed, and the mixture is heated at 100° C. in a magnetic stirring oil bath, stirred for 12 hours, and centrifuged. The obtained solid is washed with anhydrous ethanol and deionized water in turn, and dried at 60° C. for 12 hours to obtain a mercapto-functionalized transition metal oxide (mercapto-functionalized cerium oxide);

[0068] (2) Dissolve 50 mg of platinum acetylacetonate in 50 ml of deionized water, add 0.5 g of the thiol-functionalized cerium oxide obtained in step (1), sonicate for 3 hours, centrifuge, wash the solid with deionized water, and dry at 60° C. for 12 hours to obtain the thiol-functionalized cerium oxide attached with platinum.

[0069] (3) The product obtained in step (2) was placed in a tubular furnace under argon atmosphere, heated to 450°C at a rate of 10°C / min, maintained for 1 hour, cooled to room temperature, taken out, repeatedly cleaned with deionized water, and dried at 60°C for 12 hours to obtain a functionalized oxide-supported precious metal electrocatalyst (Pt@S-CeO2).

[0070] Experiments have shown that by replacing the iron oxide in Example 4 with cobalt tetroxide, cobaltous oxide, manganese dioxide, copper oxide, zinc oxide or tungsten trioxide, respectively, with the other conditions being the same as Example 4, corresponding functionalized oxide-supported precious metal electrocatalysts can be obtained.

[0071] Experiments have shown that by replacing the chloroplatinic acid in Example 4 with iridium trichloride, iridium tetrachloride, chloroiridic acid, iridium acetylacetonate or platinum chloride, the corresponding functionalized oxide-supported precious metal electrocatalysts can be obtained respectively, while the other aspects are the same as in Example 4.

[0072] Example 7

[0073] The application of the functionalized oxide-supported noble metal electrocatalyst (Ir@N-Co3O4) prepared in Example 1 in the oxygen evolution reaction (OER) comprises the following steps:

[0074] A three-electrode system was used, the electrolytic cell was a five-port electrolytic cell, the oxygen evolution reaction electrolyte was a 1M potassium hydroxide aqueous solution, the graphite rod was the counter electrode, mercury / mercuric oxide was the reference electrode, and the platinum carbon electrode (loading amount was 0.5 mg / cm2) prepared in Example 1 was drop-coated 2 ) is a working electrode;

[0075] The results are as follows Figure 4 As shown in the figure, the noble metal electrocatalyst Ir@Co3O4 directly supported by the oxide is 2 The overpotential at the current density of 10 mA / cm2 is 329 mV, and the functionalized oxide-supported noble metal electrocatalyst (Ir@N-Co3O4) has a high overpotential at 10 mA / cm2. 2 The overpotential at the current density of 254 mV is 254 mV, and the oxygen evolution reaction performance is improved by 75 mV compared with direct loading, indicating that the functionalized oxide-loaded noble metal electrocatalyst of the present invention has excellent OER catalytic performance. This catalyst can also be used in the electrocatalytic oxygen evolution of a two-electrode system, such as the anode catalyst of the electrolytic water electrolysis hydrogen production electrolyzer.

[0076] Experiments have shown that the functionalized oxide-supported noble metal electrocatalysts prepared in Examples 2-6 have a high conductivity at 10 mA / cm 2 The overpotential of the current density is similar to that of the functionalized oxide-supported noble metal electrocatalyst prepared in Example 1.

[0077] Example 8

[0078] The application of the functionalized oxide-supported noble metal electrocatalyst (Ir@N-Co3O4) prepared in Example 1 in the oxygen reduction reaction (ORR) comprises the following steps:

[0079] The oxygen reduction reaction electrolyte is 0.1M potassium hydroxide aqueous solution, the graphite rod is the counter electrode, and the silver / silver chloride is the reference electrode.

[0080] The platinum carbon electrode of the catalyst prepared in Example 1 was drip-coated as the working electrode (loading amount was 0.5 mg / cm 2 ). The result is as follows Figure 5As shown, the half-wave potential of the oxygen reduction reaction of the noble metal electrocatalyst Ir@Co3O4 directly supported by the oxide is 0.642V, and the half-wave potential of the oxygen reduction reaction of the noble metal electrocatalyst (Ir@N-Co3O4) supported by the functionalized oxide is 0.682V, and the oxygen reduction performance is improved by 40mV. This shows that the noble metal electrocatalyst supported by the functionalized oxide of the present invention has excellent ORR catalytic performance.

[0081] Experiments have shown that the half-wave potentials of the functionalized oxide-supported noble metal electrocatalysts prepared in Examples 2-6 in ORR are similar to those of the functionalized oxide-supported noble metal electrocatalysts prepared in Example 1. Among them, the Pt@S-Fe2O3 catalyst in Example 4 can be used for fuel cell cathode ORR.

[0082] Example 9

[0083] The application of the functionalized oxide-supported noble metal electrocatalyst (Ir@N-Co3O4) prepared in Example 1 in a zinc-air battery device comprises the following steps:

[0084] The positive electrode active material is oxygen in the air, the negative electrode active material is zinc flakes (purity 99.9%), and the electrolyte is an aqueous solution composed of 6M potassium hydroxide and 0.2M zinc acetate.

[0085] The electrode composite substrate (preferably Changsha Spring P1 type electrode composite substrate) is coated with the functionalized oxide-supported precious metal electrocatalyst (Ir@N-Co3O4) prepared in Example 1, with a loading of 1 mg / cm 2 In order to compare with the commercial catalyst, the catalyst was replaced with the commercial catalyst Pt / C+IrO2 with a loading of 1 mg / cm2 while keeping other test conditions the same. 2 The result is as follows Figure 6 , Figure 7 As shown, compared with the commercial catalyst Pt / C+IrO2, the precious metal electrocatalyst supported by the functionalized oxide has a higher discharge voltage, a lower charge voltage, a higher charge and discharge efficiency, and a greater power density. 2 The charge and discharge test was carried out at a current density of , and the functionalized oxide-supported precious metal electrocatalyst of the present invention has better charge and discharge stability than the commercial catalyst Pt / C+IrO2, and can be stably charged and discharged for more than 200 hours.

[0086] Experiments have shown that the power density and charge-discharge stability of the functionalized oxide-supported precious metal electrocatalysts prepared in Examples 2-6 in zinc-air battery devices are similar to those of the functionalized oxide-supported precious metal electrocatalysts prepared in Example 1 in zinc-air battery devices.

Claims

1. A method for preparing a functionalized oxide-supported noble metal electrocatalyst, characterized in that The steps include: (1) adding a transition metal oxide and a silane reagent to anhydrous ethanol, wherein the volume ratio of the silane reagent to the anhydrous ethanol is 1:(50-80), and the mass ratio of the transition metal oxide to the silane reagent is 1:(0.1-10); the silane reagent is an aminosilane reagent or a mercaptosilane reagent; heating and stirring at 60-100° C. for 12-36 hours, filtering or centrifuging, and washing the obtained solid with anhydrous ethanol and deionized water in turn, and drying to obtain an amino-functionalized transition metal oxide or a mercapto-functionalized transition metal oxide; (2) dissolving 5-50 mg of a noble metal compound in 10-50 ml of deionized water, adding 0.05-0.5 g of the amino-functionalized transition metal oxide or the thiol-functionalized transition metal oxide obtained in step (1), ultrasonicating for 0.5-3 h, filtering or centrifuging, washing the solid with deionized water, and drying to obtain an amino-functionalized transition metal oxide or a thiol-functionalized transition metal oxide attached to a noble metal; (3) annealing the product obtained in step (2) under the protection of an inert gas or nitrogen, taking it out, washing it with deionized water, and drying it to obtain a functionalized oxide-supported noble metal electrocatalyst.

2. The preparation method according to claim 1, characterized in that The transition metal oxide is cobalt tetroxide, cobaltous oxide, iron oxide, manganese dioxide, nickel oxide, copper oxide, zinc oxide, cerium oxide or tungsten trioxide.

3. The preparation method according to claim 1, characterized in that The aminosilane reagent is 3-aminopropyltriethoxysilane or N-aminoethyl-3-aminopropyltriethoxysilane.

4. The preparation method according to claim 1, characterized in that The mercaptosilane reagent is 3-mercaptopropyltriethoxysilane or mercaptopropyltrimethoxysilane.

5. The preparation method according to claim 1, characterized in that The noble metal compound is iridium trichloride, iridium tetrachloride, chloroiridic acid, iridium acetylacetonate, ruthenium chloride, platinum acetylacetonate, platinum chloride or chloroplatinic acid.

6. The preparation method according to claim 1, characterized in that The annealing in step (3) is as follows: heating to 300-450° C. at a heating rate of 3-10° C. / min, maintaining for 1-4 hours, and then cooling to room temperature.

7. A functionalized oxide-supported noble metal electrocatalyst prepared by the preparation method according to any one of claims 1 to 6.

8. Use of the functionalized oxide-supported noble metal electrocatalyst according to claim 7 in oxygen evolution reaction or oxygen reduction reaction.

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