Preparation of carbon cloth loaded co-mof nanosheet array composite material by rapid vulcanization method and application thereof

Abstract

The application discloses a kind of carbon cloth supported Co-MOF nanosheet array composite material prepared by rapid vulcanization method and application thereof, the metal cobalt salt of the present application is mixed uniformly in solution after dimethylimidazole, add a piece of carbon cloth, and stand for a period of time to obtain material precursor, flush after ending, dry, the obtained material is placed in oven and dried, to obtain the carbon cloth supported S-doped Co-MOF nanosheet array composite material.The S-doped Co-MOF nanosheet array can help material surface functionalization, improve catalytic activity, compared with prior art, the method of the present application is simple to operate, easy to scale production, and carbon cloth is beneficial to improve the conductivity and stability of material.

Description

Technical Field

[0001] This invention belongs to the field of water electrolysis catalyst technology, specifically relating to a rapid sulfidation method for preparing carbon cloth-supported Co-MOF nanosheet array composite materials and their applications. Background Technology

[0002] With the development and progress of modern society, people's demand for advanced clean energy is constantly increasing. Hydrogen, as a clean energy source, has enormous energy, abundant reserves on Earth, is renewable, and is environmentally friendly. It can serve as a substitute for fossil fuels, achieving the goal of zero carbon emissions and thus alleviating ecological and environmental pressures.

[0003] Among various hydrogen production methods, hydrogen produced by water electrolysis is highly favored as an efficient and pollution-free energy carrier. The hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode constitute the complete water electrolysis process. However, the activation energy barriers for both reactions are relatively high, making them difficult to achieve in practice both thermodynamically and kinetically. Therefore, the actual voltage of water electrolysis in actual processes is higher than its theoretical value (1.23V). To further reduce reaction energy consumption and save costs, it is necessary to develop and utilize efficient electrocatalysts to reduce the overpotential of the reaction, thereby reducing reaction energy consumption. An efficient water electrolysis catalyst is a crucial material in water electrolysis devices, determining not only the total voltage required for water electrolysis but also the efficiency of converting electrical energy into hydrogen energy. Currently, commercially available catalysts mainly focus on noble metals, such as Pt / C and RuO2, which suffer from drawbacks such as scarce reserves, high prices, and poor stability, limiting their large-scale application. This compels us to develop high-performance, highly stable non-noble metal catalysts to improve reaction kinetics, accelerate reaction rates, and reduce reaction energy consumption.

[0004] Among numerous catalysts, transition metal compounds have attracted widespread attention from researchers for their unique composition and easily tunable electronic structure in assisting water electrolysis. However, the poor conductivity of transition metal compounds makes their performance unsuitable for practical applications. Metal-organic frameworks (MOFs) are widely used as raw materials for water electrolysis. MOFs are novel porous materials with regular, tunable pores, high porosity, and large specific surface area. Therefore, MOFs possess advantages such as strong adsorption capacity, ease of modification, and abundant unsaturated metal active sites. Although MOF-based catalytic electrodes exhibit significant catalytic advantages, their complex production processes, demanding experimental conditions, and high energy input often limit their industrial applications. Therefore, if the inherent activity of catalytic electrodes can be improved simply and effectively, the application of MOF-based materials in water electrolysis will be greatly expanded.

[0005] CN111841598A discloses an S-doped Co@NC composite material with high oxygen evolution reaction (OER) catalytic activity and its preparation method. By controlling the specific surface area and crystal structure of the metal-organic framework and adjusting the content of cobalt active component and sulfur doping in nitrogen-doped porous carbon materials, the optimal crystal structure and S / N atomic ratio were found, resulting in an S-doped Co@NC composite material with excellent electrocatalytic performance. On the one hand, the composite material has a small particle size and a core-shell structure, resulting in a large specific surface area, which helps to fully expose active sites and has a larger electrochemical reaction area. On the other hand, the incorporation of S ions can improve the conductivity and interfacial charge transfer efficiency of the composite material, giving it better OER characteristics. However, this patent has a cumbersome process, uses a variety of reagents, and the material only has a single oxygen evolution reaction property, resulting in a limited functionality and a small market application. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a rapid vulcanization method for preparing carbon cloth-supported Co-MOF nanosheet array composite materials and their applications. x S y The material is gently and simply dotted on the MOF surface to form a nanoscale bamboo leaf-like morphology, providing more active sites and a larger specific surface area, which is conducive to rapid charge transfer. The method of this invention is simple to operate and easy to scale up for production; moreover, carbon cloth helps to improve the conductivity and stability of the material.

[0007] To address the problems of the existing technology, the present invention adopts the following technical solution:

[0008] A rapid vulcanization method for preparing carbon cloth-supported Co-MOF nanosheet array composite materials includes the following steps:

[0009] S1. Dissolve cobalt salt and dimethylimidazole separately in deionized water and mix them evenly. Then add carbon cloth and let it stand at room temperature to react and obtain the precursor.

[0010] S2. The precursor is placed in a solution containing a sulfiding agent and left to stand for soaking to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material.

[0011] Preferably, the cobalt salt mentioned in step S1 is selected from one or a mixture of cobalt chloride and cobalt nitrate.

[0012] Preferably, the sulfiding agent in step S2 is sodium sulfide.

[0013] Preferably, the static reaction time in step S1 is 6-12 hours.

[0014] Preferably, the molar ratio of the cobalt salt to the sulfiding agent is 1:0.5-1.

[0015] Preferably, the rapid vulcanization time in step S2 is 10 to 60 minutes.

[0016] The carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the above rapid vulcanization method.

[0017] The carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the above rapid sulfidation method is used as a catalyst in water electrolysis.

[0018] Beneficial effects:

[0019] Compared with existing technologies, the present invention provides a rapid vulcanization method for preparing carbon cloth-supported Co-MOF nanosheet array composite materials and their applications, which has the following advantages:

[0020] 1) This invention enables the simple, rapid, and scalable production of S-doped Co-MOF nanosheet array composites supported on carbon cloth. S doping modifies the surface, lowering the energy barrier, providing a high density of reaction sites, and promoting electrolyte permeation and bubble release, thus ensuring improved conductivity. Besides compositional control, structural control can also enhance the electrocatalytic performance of the material. The ample doping of CoS within the MOF framework generates more defective active sites, and the synergistic effect between the metal element, Co, and S significantly accelerates charge transfer kinetics.

[0021] 2) The reactants selected in this invention are inexpensive, the method is simple and easy to implement, the equipment is easy to set up, and large-scale production can be achieved. Carbon cloth as a carrier can effectively improve the conductivity of the material and can be directly used as a working electrode, simplifying the preparation of the working electrode. It can also avoid the use of binders and additives, and at the same time, it can prevent the aggregation of the load and improve the stability of the material.

[0022] 3) The carbon cloth-supported S-doped Co-MOF nanosheet array composite material obtained in this invention has a nanosheet array structure and features a large number of active sites, high electrocatalytic activity and high stability, which is beneficial to the diffusion of electrolyte. It is a very promising water electrolysis catalyst with broad application prospects in the future energy industry.

[0023] 4) This invention uses liquid phase sulfidation, avoiding the use of high-temperature calcination and other methods, making the preparation process more energy-efficient, low-carbon and environmentally friendly. Attached Figure Description

[0024] Figure 1The images show SEM images of S-doped Co-MOF nanosheet array composite materials prepared by the method in Example 1, which were obtained by soaking the precursor in sodium sulfide solution for 10 min, 20 min, and 30 min respectively. Among them, (a) and (b) are obtained after soaking for 10 min, (c) and (d) are obtained after soaking for 20 min, and (e) and (f) are obtained after soaking for 30 min.

[0025] Figure 2 The images show SEM images of S-doped Co-MOF nanosheet array composite materials prepared by the method in Example 1, which were obtained by soaking the precursor in sodium sulfide solution for 40 min, 50 min, and 60 min respectively. Among them, (a) and (b) are obtained after soaking for 40 min, (c) and (d) are obtained after soaking for 50 min, and (e) and (f) are obtained after soaking for 60 min.

[0026] Figure 3 The XRD pattern of the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the method in Example 1 is shown.

[0027] Figure 4 The XPS spectrum of the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the method in Example 1 is shown.

[0028] Figure 5 This is a comparison chart of the alkaline hydrogen evolution performance test data of the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the method in Example 1;

[0029] Figure 6 This is a comparison chart of alkaline oxygen evolution test data for the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the method in Example 1.

[0030] Figure 7 This is a spectrum of alkaline water-splitting performance of the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the method in Example 1. Detailed Implementation

[0031] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0032] Example 1

[0033] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0034] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm.-2 The carbon cloth was then reacted at 25°C for 6 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0035] The carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared in Example 1 was physically characterized using SEM, XRD, and XPS. Figure 1 As can be seen from the (a)-(f) and 2(a)-(f) spectra, the catalyst prepared according to the method described in Example 1 uses carbon cloth as a support and has a large number of neatly arranged nanosheet arrays grown on its surface. During the reaction, the abundant nanosheets provide a high-speed track for material transport. Figure 1 From top to bottom are scanning electron microscope images of samples obtained after soaking in 1 mol / L Na2S for 10 min, 20 min, and 30 min. As can be seen from the images, the surface of the nanosheets gradually becomes rougher with increasing sulfidation time. Figure 2 From top to bottom are scanning electron microscope images of samples obtained after soaking in 1 mol / L Na2S for 40 min, 50 min, and 60 min. As can be seen from the images, with the extension of sulfidation time, the inside of the nanosheets is etched by sodium sulfide, resulting in a hollow structure. Figure 3 The image shows the XRD pattern of the S-doped Co-MOF nanosheet composite material supported on carbon cloth. By comparing it with the standard pattern, the diffraction peaks of the material are completely consistent with the ZIF-67 standard card. Figure 4 This is the overall XPS spectrum of the S-doped Co-MOF nanosheet composite material supported on carbon cloth, in which Co, S, N, O and C elements are all present in the S-Co-MOF@CC sample.

[0036] Example 2

[0037] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0038] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2The carbon cloth was then reacted at room temperature for 7 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0039] Example 3

[0040] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0041] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 8 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 min to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0042] Example 4

[0043] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0044] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 9 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0045] Example 5

[0046] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0047] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 10 h. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 min to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0048] Example 6

[0049] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0050] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 11 h. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 min to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0051] Example 7

[0052] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0053] Weigh out 1.0 mmol CoCl2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0054] Example 8

[0055] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0056] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0057] Example 9

[0058] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0059] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 10 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0060] Example 10

[0061] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0062] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 20 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0063] Example 11

[0064] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0065] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 40 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 10 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0066] Example 12

[0067] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0068] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 50 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 10 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0069] Example 13

[0070] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0071] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 60 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in a 1.0 mol / L sodium sulfide nonahydrate solution for 10 minutes to obtain the carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0072] Example 14

[0073] A method for preparing a carbon cloth-supported S-doped Co-MOF nanosheet array composite material includes the following steps:

[0074] Weigh 1.0 mmol Co(NO3)2·6H2O and 9.0 mmol dimethylimidazole, add them separately to a certain amount of water, and stir for 30 minutes to dissolve them completely; then mix the two together and stir for 30 minutes, and add a piece of material measuring 2*4 cm. -2 The carbon cloth was then reacted at room temperature for 12 hours. After the reaction was completed, the carbon cloth sample was washed with water and ethanol in sequence. After drying, the obtained precursor was immersed in 0.5 mol / L sodium sulfide nonahydrate solution for 30 minutes to obtain carbon cloth-supported S-doped Co-MOF nanosheet array composite material. After rinsing with deionized water and ethanol and drying, the carbon cloth-supported S-doped Co-MOF nanosheet array composite material was obtained.

[0075] Comparative Example 1

[0076] Unlike Example 1, when adjusting the S doping amount, a 0.5 mol / L sodium sulfide nonahydrate solution was used for comparison with immersion and sulfidation times of 10 min to 60 min, while other steps remained unchanged.

[0077] Comparative Example 2

[0078] Unlike Example 1, sulfur doping was not performed, but the other steps remained unchanged.

[0079] The performance of composite materials prepared under different parameters was tested using the following methods:

[0080] Linear voltammetric scanning (LSV) technique was used, with a wavelength of 5 mV / s. -1 The scan rate was used to test the HER and OER of the synthesized material in 1.0 MkOH solution. The measured potentials can be converted to the reversible hydrogen electrode (RHE) scale using the following formula: ERHE =E SCE +E 0 SCE +0.059pH, where ESCE is the experimentally measured potential, E 0 SCE =0.242V. Furthermore, to eliminate the influence of ohmic resistance on the measured reaction current, iR compensation was used for all electrochemical tests. All measurements were performed at 25°C, and the results are as follows: Figure 5 and Figure 6 As shown.

[0081] Figure 5 This presents hydrogen evolution test data for Co-MOF nanosheet composites with different vulcanization times supported on carbon cloth. All electrochemical tests in this experiment were performed at room temperature using a conventional three-electrode system and a CHI760E electrochemical analyzer. Among them, 1×1cm... 2 Carbon cloth and glassy carbon electrodes constitute the working electrode, saturated calomel electrode (SCE) serves as the reference electrode, and a 6 mm graphite rod serves as the auxiliary electrode. Figure 5 Tests showed that the catalyst exhibited different electrochemical performances at different sulfidation times, i.e., different sulfur doping contents.

[0082] Figure 6 This is a comparison chart of oxygen evolution test data for Co-MOF nanosheet composites with different vulcanization times supported on carbon cloth. Similarly, in the three-electrode test system, there are significant differences in oxygen evolution performance between the unvulcanized sample and the material with different vulcanization times.

[0083] A two-electrode system was used, with both the cathode and anode made of sulfur-doped Co-MOF@CC as the working electrodes, cut to 1*1cm. -2 The carbon cloth was fixed with electrode clamps and electrochemical tests were performed in 1M KOH. The results are as follows: Figure 7 As shown, Figure 7 This is a test of the overall water-splitting performance of S-doped Co-MOF nanosheets supported on carbon cloth. The catalyst achieved a water splitting performance of 10 mA / cm². -2 Only an applied voltage of 1.55V is required. Under the same conditions, compared to the 1.60V overpotential required by commercial water electrolysis catalysts such as platinum-carbon and ruthenium dioxide, this catalyst exhibits certain application advantages. This is mainly attributed to the fact that carbon cloth improves the conductivity and stability of the material, and sulfur doping optimizes the electronic structure of the material, thereby optimizing its adsorption free energy for intermediate species in water electrolysis. This series of tests further demonstrates that this material has broad application prospects as a water electrolysis catalyst.

Claims

1. A method for preparing carbon cloth-supported S-doped Co-MOF nanosheet array composite materials, characterized in that, Includes the following steps: S1. Dissolve cobalt salt and dimethylimidazole separately in deionized water and mix them evenly. Then add carbon cloth and let it stand at room temperature to react and obtain the precursor. S2. The precursor is placed in a solution containing a sulfiding agent and allowed to stand for rapid sulfidation to obtain a carbon cloth-supported S-doped Co-MOF nanosheet array composite material; the sulfiding agent is 1 mol / L sodium sulfide, and the rapid sulfidation time is 10~60 min.

2. The method according to claim 1, characterized in that, The cobalt salt mentioned in step S1 is selected from one or a mixture of cobalt chloride and cobalt nitrate.

3. The method according to claim 1, characterized in that, The static reaction time in step S1 is 6-12 hours.

4. The method according to claim 1, characterized in that, The molar ratio of the cobalt salt and the sulfiding agent is 1:0.5-1.

5. A carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the preparation method according to any one of claims 1 to 4.

6. The application of the carbon cloth-supported S-doped Co-MOF nanosheet array composite material prepared by the preparation method of claim 1 as a catalyst in water electrolysis.

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