A AgCl-RuO2-Co3O4 / SiO2 electrocatalyst and its preparation method and application

Abstract

The present invention relates to the field of electrocatalytic oxygen evolution technology, and in particular to an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, its preparation method, and application. The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst uses a mesoporous SiO2 material as a carrier and has a nano-mesoporous structure, which ensures a large specific surface area of ​​the catalyst and is conducive to increasing the metal active sites of the catalyst. It is also loaded with AgCl, RuO2, and Co3O4 nanoparticles, with uniform catalytic particle distribution and strong catalytic activity. The electrocatalyst has an oxygen evolution overpotential as low as 20mV@10mA·cm ‑2 , having excellent acidic electrocatalytic oxygen evolution performance. The present invention also successfully prepared the electrocatalyst by combining impregnation and calcination. The method is simple, efficient, low-cost, and has the advantages of controllable preparation, making it suitable for industrial production and large-scale application.

Description

Technical Field

[0001] The present invention relates to the technical field of electrocatalytic oxygen evolution, and in particular to an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst and a preparation method and application thereof. Background Art

[0002] The oxygen evolution reaction (OER) is a key electrochemical process in zinc electrolysis. However, during the OER electron transfer process, multiple electron transfer leads to high overpotentials, resulting in a slow reaction rate. Therefore, it is necessary to develop efficient and stable OER electrocatalysts to increase the reaction rate to meet practical application requirements.

[0003] Currently, ruthenium (Ru)-based OER electrocatalysts have become mainstream due to their excellent activity and stability. However, existing OER electrocatalysts have problems such as low activity and high overpotential. In addition, Ru as a precious metal is extremely scarce, and the further promotion and application of Ru-based OER electrocatalysts are also severely restricted by the reserves and high cost of Ru itself. Therefore, the development of new OER electrocatalyst systems is extremely important. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst and its preparation method and application, aiming to solve the problems of low activity and high overpotential of existing OER electrocatalysts.

[0005] The technical solutions of the present invention are as follows:

[0006] In a first aspect of the present invention, an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst is provided, which comprises a mesoporous SiO2 material, and AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles supported on the mesoporous SiO2 material.

[0007] Optionally, the mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4).

[0008] A second aspect of the present invention provides a method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst of the present invention, comprising the steps of:

[0009] S1. Providing mesoporous SiO2 material;

[0010] S2. The mesoporous SiO2 material is prepared into a first solution, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are prepared into a second solution, the first solution and the second solution are mixed, and the mixture is impregnated, dried and calcined to obtain an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst.

[0011] Optionally, the mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4).

[0012] Optionally, the immersion temperature is 35 to 45° C., and the immersion time is 18 to 24 hours.

[0013] Optionally, the drying temperature is 120-150° C., and the drying time is 8-12 hours.

[0014] Optionally, the calcination temperature is 450-500° C., and the calcination time is 5-8 hours.

[0015] Optionally, the step of preparing the mesoporous SiO2 material into a first solution specifically includes:

[0016] The mesoporous SiO2 material is dispersed in water to prepare a first solution, wherein the mass ratio of the mesoporous SiO2 material to water is 1 mg: (10-40) g.

[0017] Optionally, the step of preparing the second solution of AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles specifically includes:

[0018] AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are dispersed in water to prepare a second solution, wherein the mass ratio of the total mass of the AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles to water is 1 mg:(20-60) g.

[0019] The third aspect of the present invention provides an application of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst of the present invention in an electrocatalytic oxygen evolution reaction in an acidic environment.

[0020] Beneficial Effects: The present invention provides an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst. The electrocatalyst uses mesoporous SiO2 as a carrier and has a nano-mesoporous structure, which ensures a large specific surface area of ​​the catalyst and helps increase the metal active sites of the catalyst. It is also loaded with AgCl, RuO2, and Co3O4 nanoparticles, resulting in a uniform distribution of catalytic particles and strong catalytic activity. The electrocatalyst has an oxygen evolution overpotential as low as 20mV@10mA·cm -2 , having excellent acidic electrocatalytic oxygen evolution performance. The present invention also successfully prepared the electrocatalyst by combining impregnation and calcination. The method is simple, efficient, low-cost, and has the advantages of controllable preparation, making it suitable for industrial production and large-scale application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the SEM image of the mesoporous SiO2 material prepared in Example 1.

[0022] Figure 2 This is the SEM image of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1.

[0023] Figure 3 This is the XRD pattern of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1.

[0024] Figure 4 This is the XPS graph of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1.

[0025] Figure 5 The current density-voltage curves of the working electrode made of the electrocatalyst prepared in Example 1, the electrocatalyst prepared in Comparative Examples 1 to 3, and the commercially available RuO2 electrocatalyst are shown.

[0026] Figure 6 This is a chronopotentiometry curve of the working electrode made of the electrocatalyst prepared in Example 1. DETAILED DESCRIPTION

[0027] The present invention provides an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, its preparation method, and application. To clarify the objectives, technical solutions, and effects of the present invention, the present invention is described in further detail below. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0028] An embodiment of the present invention provides an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, which includes a mesoporous SiO2 material, and AgCl nanoparticles, RuO2 nanoparticles, and Co3O4 nanoparticles supported on the mesoporous SiO2 material.

[0029] The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst in the embodiment of the present invention uses mesoporous SiO2 material as a carrier, has a nano-mesoporous structure, and is loaded with catalytic AgCl, RuO2 and Co3O4 nanoparticles. The catalytic particles are evenly distributed, the catalytic activity is strong, and it has excellent acidic electrocatalytic oxygen evolution performance. On the one hand, the mesoporous SiO2 material has a unique pore structure, which ensures a large specific surface area of ​​the catalyst, is conducive to increasing the metal active sites of the catalyst, improving the utilization rate of the precious metal Ru and other catalytic elements, and is also conducive to the flow of the electrolyte and the escape of oxygen in the OER reaction, thereby improving the catalytic activity of the electrocatalyst; on the other hand, the catalytic synergistic effect of the AgCl, RuO2 and Co3O4 nanoparticles can accelerate the evolution of oxygen, reduce the overpotential of the OER reaction, thereby effectively reducing power consumption and further improving the catalytic activity of the electrocatalyst. In addition, compared with existing OER electrocatalysts, the present invention introduces AgCl and Co3O4 on the mesoporous SiO2 material, and jointly regulates the catalyst performance with RuO2, thereby reducing the amount of RuO2 used and greatly improving the utilization rate of the catalytic element. Compared with commercial pure RuO2 catalysts, the cost is lower and it has good application prospects.

[0030] The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst in the embodiment of the present invention has a nano-mesoporous structure of mesoporous SiO2 material, and AgCl, RuO2 and Co3O4 nanoparticles are evenly distributed inside and outside the mesoporous SiO2 material, so that the metal elements can be maximized. The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst has excellent acidic electrocatalytic oxygen evolution performance and can be used at 10mA·cm -2 The oxygen evolution overpotential is lower than that of commercial RuO2, and the current density is stable for more than 78 hours at 10 mA·cm -2 Only 20mV is required at a current density of 1000V.

[0031] In some embodiments, the mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4).

[0032] In this embodiment, the mass ratio of the three catalytic particles (AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles) to the carrier (mesoporous SiO2 material) is mainly determined based on their own catalytic effects and the synergistic effect between the various catalytic particles. The catalyst prepared within the mass ratio range has the best catalytic effect and the oxygen evolution overpotential can reach the lowest.

[0033] An embodiment of the present invention provides a method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst described in any of the aforementioned embodiments, comprising the steps of:

[0034] S1. Providing mesoporous SiO2 material;

[0035] S2. The mesoporous SiO2 material is prepared into a first solution, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are prepared into a second solution, the first solution and the second solution are mixed, and the mixture is impregnated, dried and calcined to obtain an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst.

[0036] The embodiment of the present invention successfully prepares the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst by a method combining impregnation and calcination. First, the mesoporous SiO2 material and the AgCl, RuO2, and Co3O4 nanoparticles are dispersed in the liquid phase and then mixed. Subsequently, the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst is obtained by impregnation and high-temperature calcination. The method provided by the embodiment of the present invention is simple, efficient, low-cost, and has the advantages of controllable preparation, which is suitable for industrial production and large-scale application. The electrocatalyst finally prepared also has the nano-mesoporous structure of the mesoporous SiO2 material, and the catalytic AgCl, RuO2, and Co3O4 nanoparticles are evenly distributed, have strong catalytic activity, and have excellent acidic electrocatalytic oxygen evolution performance.

[0037] In step S1, in some embodiments, the mesoporous SiO2 material can be directly purchased or prepared using conventional methods in the art, which is not limited here.

[0038] In some preferred embodiments, the method for preparing the mesoporous SiO2 material comprises the steps of:

[0039] Pluronic F127, water and hydrochloric acid are mixed and stirred to obtain a transparent solution, and then n-butanol and ethyl orthosilicate are added and stirred, and a mesoporous SiO2 material is obtained through a hydrothermal reaction.

[0040] In this embodiment, the surfactant Pluronic F127, water and hydrochloric acid are first mixed and stirred to obtain a transparent solution, and then n-butanol and ethyl orthosilicate are added in sequence and mixed and stirred, and then a mesoporous SiO2 material is obtained through a hydrothermal reaction. The prepared mesoporous SiO2 material is small in size and has a unique pore structure, which ensures a larger specific surface area of ​​the catalyst and is beneficial to increasing the metal active sites of the catalyst.

[0041] In this embodiment, Pluronic F127, also known as Poloxamer F127, is a nonionic surfactant belonging to the Pluronic polymer family. Pluronic F127 is composed of blocks of two different polymers, polyoxyethylene (PEO) and polyoxypropylene (PPO), forming a triblock structure, typically represented as PEO-PPO-PEO.

[0042] In this embodiment, the mass ratio of Pluronic F127, water, and hydrochloric acid is (1-5):(100-150):(10-25). Within this mass ratio range, a mesoporous SiO2 material with a pore microstructure can be successfully prepared.

[0043] In this embodiment, the concentration of the hydrochloric acid is 36% to 38%, wherein the concentration of the hydrochloric acid is a mass percentage concentration.

[0044] In this embodiment, the volume ratio of n-butanol to tetraethyl orthosilicate is (8-13):(10-20). Within this volume ratio range, SiO2 material with a pore microstructure can be successfully prepared.

[0045] In this embodiment, the hydrothermal reaction temperature is 120-150° C. and the reaction time is 20-24 hours. Within the reaction temperature and time range, the material can be fully aged, resulting in a smaller particle size of the calcined SiO 2 material.

[0046] In some embodiments, the step of mixing Pluronic F127, water, and hydrochloric acid to obtain a transparent solution, then adding n-butanol and ethyl orthosilicate, mixing, and obtaining the mesoporous SiO2 material through a hydrothermal reaction specifically includes:

[0047] Pluronic F127, water and hydrochloric acid were mixed and stirred at room temperature for 1 to 2 hours to obtain a transparent solution, n-butanol was then added and stirred at room temperature for 0.5 to 1 hour, and then ethyl orthosilicate was added and stirred at 38 to 42°C for 22 to 26 hours to obtain a mesoporous SiO2 material through a hydrothermal reaction.

[0048] In step S2, in some embodiments, the mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles, and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4). Within this mass ratio range, the three catalytic particles can be fully mixed with the mesoporous SiO2 material, and the synergistic effect between the catalytic particles is optimized, thereby achieving the best catalytic effect of the catalyst.

[0049] In some preferred embodiments, the mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is 2:2:3:3.

[0050] In some embodiments, the impregnation temperature is 35 to 45° C., and the impregnation time is 18 to 24 hours. The present invention uses an impregnation method to uniformly load AgCl nanoparticles, RuO2 nanoparticles, and Co3O4 nanoparticles on a mesoporous SiO2 material. Within the impregnation temperature and time range, the three catalytic particles can be evenly dispersed inside and outside the SiO2 material, maximizing the utilization of the catalytic metal elements.

[0051] In some embodiments, the drying temperature is 120-150° C., and the drying time is 8-12 hours. The purpose of the drying is to collect the powdered material. Within the drying temperature and time range, the moisture inside and outside the material can be effectively dried, and the material is fully ground to obtain a powdered material.

[0052] In some embodiments, the calcination temperature is 450-500°C, the calcination time is 5-8 hours, and the calcination heating rate is 5-10°C / min. The purpose of the calcination is to remove the organic mesoporous SiO2 material. Within the calcination temperature and time range, the mesoporous SiO2 material can effectively undergo a combustion reaction. After calcination, the catalyst is effectively free of organic matter, while still retaining the pore microstructure of the mesoporous SiO2.

[0053] In some embodiments, the step of preparing the mesoporous SiO2 material into a first solution specifically includes:

[0054] The mesoporous SiO2 material is dispersed in water (preferably distilled water) to prepare a first solution, wherein the mass ratio of the mesoporous SiO2 material to water is 1 mg: (10-40) g.

[0055] In some preferred embodiments, the mass ratio of the mesoporous SiO2 material to water is 1 mg:20 g.

[0056] In some embodiments, the step of preparing the second solution of AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles specifically includes:

[0057] AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are dispersed in water (preferably distilled water) to prepare a second solution, wherein the mass ratio of the total mass of AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles to water is 1 mg: (20-60) g.

[0058] In some preferred embodiments, the mass ratio of the total mass of the AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles to water is 1 mg:40 g.

[0059] An embodiment of the present invention provides an application of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst described in any of the aforementioned embodiments in an electrocatalytic oxygen evolution reaction in an acidic environment.

[0060] The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst in the embodiment of the present invention has excellent acidic electrocatalytic oxygen evolution performance and can be used in the electrocatalytic reaction at 10 mA·cm -2 The oxygen evolution overpotential is lower than that of commercial RuO2, and the current density is stable for more than 78 hours at 10 mA·cm -2 Only 20mV is required at a current density of 1000V.

[0061] The present invention will be further described below with reference to specific examples.

[0062] Example 1

[0063] This embodiment provides a method for preparing an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, which is as follows:

[0064] (1) 3.0 g of Pluronic F127, 144 g of distilled water, and 16.4 g of hydrochloric acid were mixed at room temperature and stirred using a magnetic stirrer for 1 h until a transparent solution was formed. 11.0 mL of n-butanol was added as a cosolvent and stirring was continued for about 0.5 h. Then, 15.3 mL of tetraethyl orthosilicate (TEOS) was added and the mixture was stirred at 40 °C for 24 h to obtain a mixture.

[0065] (2) The mixture obtained in step (1) was transferred to a 250 mL Teflon-lined reactor and placed in a drying oven at 150° C. for hydrothermal reaction treatment for 24 h. The mixture was then washed with ethanol and distilled water and filtered, and then dried overnight to obtain a mesoporous SiO2 material.

[0066] (3) The mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles obtained in step (2) are weighed separately in a mass ratio of 2:2:3:3, 2 mg of the mesoporous SiO2 material is dispersed in distilled water with a solid-liquid ratio of 1 mg:20 g to prepare a mesoporous SiO2 material solution, and 8 mg of the total mass of AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are dispersed in distilled water with a solid-liquid ratio of 1 mg:40 g to prepare an AgCl-RuO2-Co3O4 solution, which is stirred for about 1 hour.

[0067] (4) The AgCl-RuO2-Co3O4 solution obtained in step (3) was mixed into the mesoporous SiO2 material solution, first immersed and stirred at 40°C for 24 hours, then dried at 130°C for 12 hours, and finally calcined at 450°C for 6 hours to obtain the final product AgCl-RuO2-Co3O4 / SiO2 electrocatalyst.

[0068] Comparative Example 1

[0069] This comparative example provides a method for preparing a RuO2-Co3O4 / SiO2 electrocatalyst, which is as follows:

[0070] (1) The mesoporous SiO2 material was prepared by the same steps as steps (1) and (2) in Example 1.

[0071] (2) The prepared mesoporous SiO2 material, RuO2 nanoparticles and Co3O4 nanoparticles were weighed according to a mass ratio of 2:5:3, 2 mg of mesoporous SiO2 material was dispersed in distilled water with a solid-liquid ratio of 1 mg:20 g to prepare a mesoporous SiO2 material solution, and 8 mg of RuO2 nanoparticles and Co3O4 nanoparticles were dispersed in distilled water with a solid-liquid ratio of 1 mg:40 g to prepare a RuO2-Co3O4 solution, which was stirred for about 1 hour.

[0072] (3) The RuO2-Co3O4 solution obtained in step (2) was mixed into the mesoporous SiO2 material solution, first immersed and stirred at 40°C for 24 hours, then dried at 130°C for 12 hours, and finally calcined at 450°C for 6 hours to obtain the final product RuO2-Co3O4 / SiO2 electrocatalyst.

[0073] Comparative Example 2

[0074] This comparative example provides a method for preparing a RuO2 / SiO2 electrocatalyst, which is as follows:

[0075] (1) The mesoporous SiO2 material was prepared by the same steps as steps (1) and (2) in Example 1.

[0076] (2) The prepared mesoporous SiO2 material and RuO2 nanoparticles were weighed separately in a mass ratio of 2:8, 2 mg of mesoporous SiO2 material was dispersed in distilled water with a solid-liquid ratio of 1 mg:20 g to prepare a mesoporous SiO2 material solution, and 8 mg of RuO2 was dispersed in distilled water with a solid-liquid ratio of 1 mg:40 g to prepare a RuO2 solution, and stirred for about 1 hour.

[0077] (3) The RuO2 solution obtained in step (2) was mixed into the mesoporous SiO2 material solution, first immersed and stirred at 40°C for 24 hours, then dried at 130°C for 12 hours, and finally calcined at 450°C for 6 hours to obtain the final product RuO2 / SiO2 electrocatalyst.

[0078] Comparative Example 3

[0079] This comparative example provides a preparation method of RuO2-Co3O4 electrocatalyst, which is as follows:

[0080] (1) Weigh 5 mg of RuO2 nanoparticles and 3 mg of Co3O4 nanoparticles at a mass ratio of 5:3, add them to distilled water at a solid-liquid ratio of 1 mg:40 g to prepare a RuO2-Co3O4 solution.

[0081] (3) The RuO2-Co3O4 solution obtained in step (1) was immersed and stirred at 40°C for 24 hours, then dried at 130°C for 12 hours, and finally calcined at 450°C for 6 hours to obtain the final product RuO2-Co3O4 electrocatalyst.

[0082] The following microstructure and morphology tests were performed on the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1, and the OER (oxygen evolution reaction) performance characterization was performed on the electrocatalysts prepared in Example 1, Comparative Examples 1 to 3, and a commercially available RuO2 electrocatalyst (Shanghai MacLean Biotechnology Co., Ltd., CAS No. 12036-10-1).

[0083] 1. The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1 was tested for its microstructure and morphology using an X-ray diffractometer and a field emission scanning electron microscope.

[0084] Figure 1 3 is a scanning electron microscope (SEM) image of the mesoporous SiO2 material prepared in Example 1. It can be seen from the image that the mesoporous SiO2 material has a uniformly distributed pore structure.

[0085] Figure 2This is the SEM image of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1. According to the figure, the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1 is relatively uniform, has good crystallinity, and retains the pore microstructure of the carrier mesoporous SiO2 material.

[0086] Figure 3 This is the X-ray diffraction (XRD) pattern of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1. Strong and broad diffraction peaks of AgCl, RuO2 and Co3O4 appear in the pattern, which indicates that the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1 has good crystallinity and small particle size.

[0087] Figure 4 This is the X-ray photoelectron spectroscopy (XPS) diagram of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1. The diagram shows the chemical composition of AgCl, RuO2, and Co3O4. It can be seen that Ag exists in a +1 chemical valence state, Ru and Co exist only in the form of oxides, most of ruthenium exists in a +4 chemical valence state, and Co 2p 3 / 2 and Co 2p 1 / 2 The spin states of Co are indexed at 781.2 eV and 796.5 eV, respectively, indicating that the Co element exists in two chemical valence states of +2 and +3.

[0088] 2. The OER performance of the electrocatalysts prepared in Example 1 and Comparative Examples 1 to 3, as well as the commercially available RuO2 electrocatalyst, was characterized as follows:

[0089] The electrocatalysts prepared in Example 1 and Comparative Examples 1 to 3, as well as commercially available RuO2 electrocatalysts, were made into corresponding working electrodes:

[0090] (1) 10 mg of the electrocatalyst prepared in Example 1, the electrocatalyst prepared in Comparative Examples 1 to 3, and the commercially available RuO2 electrocatalyst were respectively weighed and placed in different 1 mL centrifuge tubes. 100 uL of ethanol, 50 uL of 5 wt.% Nafion solution, and 50 uL of isopropanol were respectively transferred thereto using a pipette, and then ultrasonicated for 1 hour to form a uniformly dispersed suspension, wherein the electrocatalyst prepared in Example 1 was correspondingly prepared into suspension L1, the electrocatalysts prepared in Comparative Examples 1 to 3 were respectively prepared into suspensions L2, L3, and L4, and the commercially available RuO2 electrocatalyst was correspondingly prepared into suspension L5.

[0091] (2) The surfaces of five glassy carbon electrodes (surface area 0.196 cm) were treated with anhydrous ethanol and distilled water. 2) were ultrasonically treated and dried naturally for later use. 5uL of the above suspensions L1, L2, L3, L4, and L5 were then pipetted and added dropwise three times to the corresponding glassy carbon electrode surfaces. The electrodes were then dried naturally to obtain five working electrodes, of which the electrocatalyst prepared in Example 1 was used to make the working electrode WE1, the electrocatalysts prepared in Comparative Examples 1 to 3 were used to make the working electrodes WE2, WE3, and WE4, respectively, and the commercially available RuO2 electrocatalyst was used to make the working electrode WE5.

[0092] OER performance characterization test method: using a standard three-electrode system at 1 mol·L -1 Electrochemical OER performance was tested in H₂SO₄ solution using the working electrodes WE1, WE2, WE3, WE4, and WE5 obtained above as working electrodes, a platinum electrode as the counter electrode, and a saturated mercurous sulfate electrode as the reference electrode. Linear cyclic voltammetry (LSV) was used to measure polarization curves under the following conditions: a sweep voltage range of -0.5 to 1.5 V (vs. SCE) at a sweep rate of 0.01 V / s. iR (internal resistance) compensation was not performed on all LSV test data.

[0093] Test results: Figure 5 The current density-voltage curves of the working electrodes prepared by the electrocatalyst prepared in Example 1, the electrocatalyst prepared in Comparative Examples 1 to 3, and a commercially available RuO2 electrocatalyst are shown in Table 1. The oxygen evolution overpotentials of the electrocatalyst prepared in Example 1, the electrocatalyst prepared in Comparative Examples 1 to 3, and a commercially available RuO2 electrocatalyst are shown in Table 1. Figure 6 This is a chronopotentiometry curve of the working electrode made of the electrocatalyst prepared in Example 1.

[0094] Table 1 Oxygen evolution overpotential of different electrocatalysts

[0095]

[0096]

[0097] According to Table 1, Figure 5 and Figure 6 It can be seen that the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1 of the present invention has a high conductivity at 10 mA·cm -2At a current density of 100 nm, the oxygen evolution overpotential is only 20 mV, which is about 200 mV lower than that of the commercial RuO2 electrocatalyst and much lower than that of the other electrocatalysts in Comparative Examples 1 to 3. In addition, during the chronopotentiometry test, the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst prepared in Example 1 can maintain a stable potential for more than 78 h @ 10 mA·cm -2 These data indicate that the electrocatalytic oxygen evolution performance of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst of the present invention in an acidic environment is superior to that of RuO2-Co3O4 / SiO2, RuO2 / SiO2, RuO2-Co3O4 and commercially available RuO2 electrocatalysts. A synergistic effect exists among the AgCl, RuO2 and Co3O4 nanoparticles, and the introduction of the carrier mesoporous SiO2 material can improve the utilization rate of the precious metal Ru and other catalytic elements, accelerate the precipitation of O2, greatly reduce the overpotential of the OER reaction, and significantly improve the catalyst activity.

[0098] In summary, the present invention provides an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, which uses a mesoporous SiO2 material as a carrier and is loaded with AgCl, RuO2 and Co3O4 nanoparticles. On the one hand, the mesoporous SiO2 material has a unique pore structure, which ensures a large specific surface area of ​​the catalyst, is beneficial to increase the metal active sites of the catalyst, improves the utilization rate of the precious metal Ru and other catalytic elements, and is also beneficial to the flow of the electrolyte and the escape of oxygen in the OER reaction, thereby improving the catalytic activity of the electrocatalyst; on the other hand, the catalytic synergistic effect of the AgCl, RuO2 and Co3O4 nanoparticles can accelerate the precipitation of oxygen, reduce the overpotential of the OER reaction, thereby effectively reducing power consumption and further improving the catalytic activity of the electrocatalyst.

[0099] It should be understood that the application of the present invention is not limited to the above examples. For those skilled in the art, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. An AgCl-RuO2-Co3O4 / SiO2 electrocatalyst, characterized in that: It includes mesoporous SiO2 material, and AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles loaded on the mesoporous SiO2 material; The preparation steps of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst include: S1. Providing mesoporous SiO2 material; S2, preparing the mesoporous SiO2 material into a first solution, preparing AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles into a second solution, mixing the first solution and the second solution, and performing impregnation, drying and calcination to obtain an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst; The calcination temperature is 450-500° C., and the calcination time is 5-8 hours.

2. The AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 1, characterized in that The mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4).

3. A method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 1 or 2, characterized in that: Including steps: S1. Providing mesoporous SiO2 material; S2, preparing the mesoporous SiO2 material into a first solution, preparing AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles into a second solution, mixing the first solution and the second solution, and performing impregnation, drying and calcination to obtain an AgCl-RuO2-Co3O4 / SiO2 electrocatalyst; The calcination temperature is 450-500° C., and the calcination time is 5-8 hours.

4. The method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 3, characterized in that: The mass ratio of the mesoporous SiO2 material, AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles is (1-3):(1.5-2.5):(2.5-3.5):(2-4).

5. The method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 3, characterized in that: The immersion temperature is 35-45° C., and the immersion time is 18-24 hours.

6. The method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 3, characterized in that: The drying temperature is 120-150° C., and the drying time is 8-12 hours.

7. The method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 3, characterized in that: The step of preparing the mesoporous SiO2 material into a first solution specifically includes: The mesoporous SiO2 material is dispersed in water to prepare a first solution, wherein the mass ratio of the mesoporous SiO2 material to water is 1 mg: (10-40) g.

8. The method for preparing the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst according to claim 3, characterized in that: The step of preparing the second solution of AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles specifically comprises: AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles are dispersed in water to prepare a second solution, wherein the mass ratio of the total mass of the AgCl nanoparticles, RuO2 nanoparticles and Co3O4 nanoparticles to water is 1 mg:(20-60) g.

9. Use of the AgCl-RuO2-Co3O4 / SiO2 electrocatalyst as claimed in claim 1 or 2 in electrocatalytic oxygen evolution reaction under acidic environment.

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