Preparation method and application of bifunctional S / Fe-CoMoO4 electro-catalytic material
By introducing Fe3+ on CoMoO4 nanoflowers and vulcanizing, a dual-function S/Fe-CoMoO4 electrocatalytic material was prepared, which solved the problem of insufficient performance of existing electrocatalysts, and achieved excellent performance in HER and OER and the potential for industrial applications.
Patent Information
- Application Number
- CN202510355482.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-25
- Publication Date
- 2025-06-27
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing electrocatalysts have not yet met the practical application requirements in terms of performance, especially in terms of cost and efficiency, which limits the large-scale application of hydrogen carbon-free energy.
Dual-function S/Fe-CoMoO4 electrocatalytic material was prepared by hydrothermal method, self-sacrificial template and tubular furnace vulcanization method. The catalyst introduced Fe3+ on CoMoO4 nanoflowers and vulcanized to form a flower-like structure to improve the electrochemically active site and mass diffusion kinetics.
The catalyst has achieved excellent performance in hydrogen regeneration reaction (HER) and oxygen evolution reaction (OER), has good activity and stability, is suitable for industrial applications, and has good circulation performance and will not cause secondary pollution to the environment.
Smart Images
Figure CN120210873A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electrocatalytic materials, and particularly relates to a preparation method and application of a bifunctional S / Fe-CoMoO4 electrocatalytic material. Background Art
[0002] Improving the utilization rate of hydrogen, a carbon-free energy source, will have a positive improvement effect on the current global energy crisis. Electrocatalytic overall water splitting technology, as a method for producing green hydrogen by electrolyzing water, has received widespread attention for its application potential. However, the implementation of this technology is restricted by the cost of catalysts. Currently, the dominant catalysts for water electrolysis are mainly precious metal catalysts with high value, such as Pt / C, RuO2, IrO2, etc., which undoubtedly greatly increases the cost of hydrogen production, thus severely restricting the large-scale application of hydrogen energy. Therefore, researchers are committed to designing and developing an economical and efficient catalyst, and a large number of related studies have emerged, such as transition metal oxides, transition metal hydroxides, single-atom catalysts, and non-metal catalysts. Nevertheless, the existing electrocatalysts have not yet met the requirements of practical applications, so the development of efficient electrocatalysts is particularly important.
[0003] Among many transition metal oxide electrocatalysts, CoMoO4 is regarded as a electrocatalyst with great potential due to its excellent redox ability, high electronic conductivity, and high structural stability. Unfortunately, although transition metal molybdate composites show potential in the field of high-performance catalysis, their practical applications are limited by a series of inherent defects, such as low conductivity, scarcity of active sites, and limited specific surface area. To overcome these limitations, heteroatom doping has been proposed and applied to optimize the electronic properties of electrocatalysts, thereby increasing the number of electrochemically active sites. This strategy has been proven to have a significant effect in enhancing the electrocatalytic activity in the hydrogen evolution reaction (HER). Especially in molybdate compounds, the octahedral Fe 3+ sites can strongly adsorb a variety of oxygen-containing intermediates due to their short Fe-O bond length, thus significantly enhancing the activity of the oxygen evolution reaction (OER). Further studies have shown that the doping of Fe not only enhances the covalent interaction between the active site and oxygen atoms, but also improves the basic properties of oxygen, thereby further promoting the improvement of OER activity. Summary of the Invention
[0004] The purpose of the present invention is to solve the disadvantages existing in the prior art, and to propose a preparation method and application of a bifunctional S / Fe-CoMoO4 electrocatalytic material. The bifunctional S / Fe-CoMoO4 electrocatalytic material is prepared by a hydrothermal method, a self-sacrificial template, and a tube furnace sulfidation method. The catalyst has excellent HER performance, OER performance, and stability, and has good application prospects in industry.
[0005] To achieve the above object, the present invention adopts the following technical solutions:
[0006] A preparation method of a bifunctional S / Fe-CoMoO4 electrocatalytic material, wherein the microscopic morphology of the S / Fe-CoMoO4 electrocatalytic material is attached to the surface of cobalt molybdate nanosheets in the form of ultrathin nanosheets, and the method includes the following steps:
[0007] Step 1: Dissolve 1.4 g - 1.6 g of Co(NO3)2·6H2O and 0.8 g - 0.9 g of (NH4)6Mo7O 24 ·4H2O in 25 mL of distilled water. At the same time, 1.1 g - 1.3 g of CO(NH2)2 is added as a surfactant; the entire solution system is magnetically stirred for 30 minutes to form a uniform mixed solution; subsequently, the above mixed solution is transferred to a 50 mL polytetrafluoroethylene-lined autoclave, and the treated nickel foam is immersed therein; then the autoclave is sealed at 120 °C for 10 h, washed several times with deionized water and ethanol until neutral, and dried in vacuum to obtain CoMoO4 / NF;
[0008] Step 2: Transfer a piece of CoMoO4 / NF obtained in the above Step 1 and an aqueous solution of K3[Fe(CN)6] to a 50 mL Teflon liner, and carry out the reaction at 85 °C for 2 - 3 hours; after naturally cooling to room temperature, take out the product, wash it several times with deionized water and ethanol until neutral, and dry it in vacuum to obtain PBA / CoMoO4 / NF;
[0009] Step 3: Place sulfur powder upstream of the obtained PBA / CoMoO4 / NF and place it in a tubular furnace. Preferably, in Step 1, the size of the nickel foam is (1 - 2) × (2 - 3) cm 2 , and the nickel foam should be ultrasonically treated in a 2 - 4 mol / L HCl solution of 50 - 100 ml for 5 - 15 minutes.
[0010] Preferably, in Step 2, the concentration of the aqueous solution of K3[Fe(CN)6] is 4 mg mL -1 -12 mg mL -1 .
[0011] Preferably, in Step 3, the mass of the sulfur powder is 0.5 - 3 g.
[0012] Preferably, in Step 3, the sulfidation temperature is 300 - 450 °C, the heat preservation time is 1 - 3 h, and the heating rate is 0.5 - 2 °C / min.
[0013] Preferably, in Steps 1, 2 and 3, the washing is carried out 3 - 5 times with deionized water and ethanol.
[0014] Preferably, in Steps 1, 2 and 3, drying is carried out in a vacuum oven at a temperature of 50-80 °C for 6-12 h.
[0015] The present invention also provides an application of the bifunctional S / Fe-CoMoO4 electrocatalytic material prepared by the above preparation method in the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER).
[0016] By adopting the above technical solution: the catalyst is obtained by first introducing Fe into CoMoO4 through a self-sacrificial template on CoMoO4 nanoflowers and then performing sulfidation. The flower-like structure endows the catalyst with rich electrochemically active sites and enhanced mass diffusion kinetics. Benefiting from the coupling effect of Fe and S co-doping, the synthesized S / Fe-CoMoO4 has good HER (42 mV@10 mA cm 3+ ) and OER (177 mV@10 mA cm -2 ) activities. This design and synthesis provide a new approach for the preparation of high-performance transition metal-based electrocatalysts required for large-scale industrial hydrogen production. -2 ) activity. This design and synthesis provide a new approach for the preparation of high-performance transition metal-based electrocatalysts required for large-scale industrial hydrogen production.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] 1. The present invention prepares a bifunctional S / Fe-CoMoO4 electrocatalytic material by a self-sacrificial template and a tube furnace sulfidation method. The catalyst has excellent HER performance, OER performance and stability.
[0019] 2. The S / Fe-CoMoO4 electrocatalytic material prepared by the present invention has good cycling performance and can be continuously applied for a long time without causing secondary pollution to the environment during the application process.
[0020] 3. The preparation method of the present invention is simple to operate, has low raw material cost, is environmentally friendly and has the potential for large-scale production, which is beneficial to industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 is the XRD pattern of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention;
[0022] Figure 2 is the SEM photograph of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention;
[0023] Figure 3 is the TEM photograph of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention;
[0024] Figure 4HRTEM image of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention;
[0025] Figure 5 XPS spectrum of the highly stable bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention;
[0026] Figure 6 LSV curve of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention for OER performance in 1 M KOH environment;
[0027] Figure 7 LSV curve of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention for HER performance in 1 M KOH environment;
[0028] Figure 8 Comparison chart of LSV after 5000 cv of the bifunctional S / Fe-CoMoO4 electrocatalyst prepared in Example 1 of the present invention in 1 M KOH environment. Detailed implementation mode
[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, so that those skilled in the art can better understand the advantages and features of the present invention, and thus more clearly define the protection scope of the present invention. The embodiments described in the present invention are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the protection scope of the present invention.
[0030] Reagents:
[0031] Ethanol, sulfur, cobalt nitrate hexahydrate, urea, ammonium molybdate tetrahydrate, and potassium ferricyanide were all purchased from Shanghai Merck Chemical Technology Co., Ltd.
[0032] The water used in the experiment was all deionized water. Unless otherwise specified, other chemical reagents were of analytical grade and did not require further purification and treatment and could be used directly.
[0033] Example 1:
[0034] A preparation method of a bifunctional S / Fe-CoMoO4 electrocatalytic material, comprising the following steps:
[0035] (1) Dissolve 1.5 g of Co(NO3)2·6H2O and 0.85 g of (NH4)6Mo7O in 25 mL of distilled water 24An aqueous solution of ·4H2O. Meanwhile, 1.2 g of CO(NH2)2 was added as a surfactant; the entire solution system was magnetically stirred for 30 minutes to form a homogeneous mixed solution; subsequently, the above mixed solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave, and the treated nickel foam was immersed therein; then the autoclave was sealed at 120 °C for 10 h, washed several times with deionized water and ethanol until neutral, and dried in vacuo to obtain CoMoO4 / NF.
[0036] (2) Transfer a piece of the obtained CoMoO4 / NF and 4 mg ml -1 aqueous solution of K3[Fe(CN)6] to a 100 mL polytetrafluoroethylene inner lining and carry out the process at 85 °C for 2 h. After naturally cooling to room temperature, take it out and wash it several times with deionized water and ethanol until neutral. Dry it in a vacuum drying oven at 80 °C overnight to obtain PBA / CoMoO4 / NF.
[0037] (3) Weigh 1.2 g of sulfur powder and place it upstream of the obtained PBA / CoMoO4 / NF, and place it in a tubular furnace. Under the condition of continuous N2 flow, heat the tubular furnace to 350 °C, keep it warm for 1 h, and the heating rate is 2 °C / min. Finally, wash the nickel foam and dry it overnight in a vacuum oven at 60 °C to obtain S / Fe-CoMoO4.
[0038] Example 2:
[0039] A preparation method of a bifunctional S / Fe-CoMoO4 electrocatalytic material, comprising the following steps:
[0040] (1) Dissolve 1.6 g of Co(NO3)2·6H2O and 0.9 g of (NH4)6Mo7O 24 in 25 mL of distilled water to obtain an aqueous solution of ·4H2O. Meanwhile, 1.3 g of CO(NH2)2 was added as a surfactant; the entire solution system was magnetically stirred for 30 minutes to form a homogeneous mixed solution; subsequently, the above mixed solution was transferred to a 50 mL polytetrafluoroethylene-lined autoclave, and the treated nickel foam was immersed therein; then the autoclave was sealed at 120 °C for 10 h, washed several times with deionized water and ethanol until neutral, and dried in vacuo to obtain CoMoO4 / NF.
[0041] (2) Transfer a piece of the obtained CoMoO4 / NF and 8 mgml -1 aqueous solution of K3[Fe(CN)6] to a 100 mL polytetrafluoroethylene inner lining and carry out the process at 85 °C for 2 h. After naturally cooling to room temperature, take it out and wash it several times with deionized water and ethanol until neutral. Dry it in a vacuum drying oven at 80 °C overnight to obtain PBA / CoMoO4 / NF.
[0042] (3) Weigh 0.6 g of sulfur powder and place it upstream of the obtained PBA / CoMoO4 / NF above, and place it in a tubular furnace. Under the condition of continuous N2 flow, heat the tubular furnace to 300 °C, keep it warm for 1 h, and the heating rate is 2 °C / min. Finally, wash the nickel foam and dry it overnight in a vacuum oven at 60 °C to obtain S / Fe-CoMoO4.
[0043] Example 3:
[0044] A preparation method of a bifunctional S / Fe-CoMoO4 electrocatalytic material, comprising the following steps:
[0045] (1) Dissolve 1.4 g of Co(NO3)2·6H2O and 0.8 g of (NH4)6Mo7O 24 ·4H2O in 25 mL of distilled water. At the same time, add 1.1 g of CO(NH2)2 as a surfactant; magnetically stir the entire solution system for 30 minutes to form a homogeneous mixed solution; then transfer the above mixed solution to a 50 mL polytetrafluoroethylene-lined autoclave, and immerse the treated nickel foam into it; then seal the autoclave at 120 °C for 10 h, wash it several times with deionized water and ethanol until neutral, and dry it in vacuum to obtain CoMoO4 / NF.
[0046] (2) Transfer a piece of the obtained CoMoO4 / NF above and 2 mgml -1 K3[Fe(CN)6] aqueous solution to a 100 mL polytetrafluoroethylene inner liner and carry out for 2 h at 85 °C. After naturally cooling to room temperature, take it out and wash it several times with deionized water and ethanol until neutral. Dry it overnight in a vacuum drying oven at 80 °C to obtain PBA / CoMoO4 / NF.
[0047] (3) Weigh 1.8 g of sulfur powder and place it upstream of the obtained PBA / CoMoO4 / NF above, and place it in a tubular furnace. Under the condition of continuous N2 flow, heat the tubular furnace to 400 °C, keep it warm for 1 h, and the heating rate is 2 °C / min. Finally, wash the nickel foam and dry it overnight in a vacuum oven at 60 °C to obtain S / Fe-CoMoO4.
[0048] The X-ray diffraction spectrum (XRD) of the electrocatalytic material S / Fe-CoMoO4 prepared in Example 1 is as Figure 1 shown. Figure 1 It can be seen that the diffraction peaks correspond to the active species of CoMoO4 (PDF#21-0868) and MoS2 (PDF#06-0097) respectively.
[0049] The SEM image of the electrocatalytic material S / Fe-CoMoO4 prepared in Example 1 is as Figure 2 shown. In Figure 2The morphologies of the precursor CoMoO4 nanoflowers, PBA / CoMoO4, and the final material S / Fe-CoMoO4 were characterized. In Figure 2 In the a image, nanorod-like CoMoO4 is densely and uniformly arranged on the NF substrate, forming hierarchical microspheres with an average diameter of 10 - 20 μm. After soaking the CoMoO4 precursor in an aqueous solution of K3[Fe(CN)6], it still maintains the nanoflower structure Figure 2 b. The prepared S / Fe-CoMoO4 still exhibits a uniformly distributed and smooth flower-like structure after subsequent thermal sulfidation treatment Figure 2 c.
[0050] The TEM of the electrocatalytic material of S / Fe-CoMoO4 prepared in Example 1 is as Figure 3 shown. The TEM image in Figure 3 further confirms the morphology of the S / Fe-CoMoO4 nanoflowers.
[0051] The HRTEM image of the electrocatalytic material of S / Fe-CoMoO4 prepared in Example 1 is as Figure 4 shown. Figure 4 The HRTEM image in
[0052] further proves the existence of these phases. Among them, 0.199 nm and 0.324 nm correspond to the (-511) plane and (-202) plane of CoMoO4 (PDF#21 - 0868), and the (311) plane and (006) of MoS2 (PDF#06 - 0097), respectively. Figure 5 shown. In Figure 5 a, it is not difficult to see that Co, Mo, S, Fe, and O elements all exist in the S / Fe-CoMoO4 nanocomposite prepared in the present invention. Figure 5 b - d show the high-resolution photoelectron spectra of Co2p, Mo3d, S2p, Fe2p, and O1S. The high-resolution spectrum of Co 2p shows that the strong peaks near 781.3 eV, 786.8 eV, 795 eV, and 803.2 eV are respectively attributed to Co 2p 3 / 2 , Co 2p 3 / 2 , Co 2p 1 / 2 and Co 2p 1 / 2 . The high-resolution spectrum of Mo 3d shows that the strong peaks near 225.5 eV and 232 eV are respectively attributed to Mo 3d 3 / 2 , Mo 3d 5 / 2 . The high-resolution spectrum of Fe2p shows that the strong peaks near 705.9 eV, 711.1 eV, and 723.9 eV are respectively attributed to Fe2p3 / 2 , Fe2p 3 / 2 and Fe 2p 1 / 2 . According to the high-resolution photoelectron spectrum of S2p, the peak at 167.9 eV belongs to the S-O component, while the peaks at 162.8 eV and 161.5 eV belong to S2p 1 / 2 and S2p 3 / 2 . The high-resolution spectrum of O 1s shows that there is a strong peak at 532.1 eV, confirming the existence of the -OH functional group, while the peak at 529.6 eV is related to the defective oxygen atoms present in CoMoO4.
[0053] The LSV curve of the electrocatalytic material S / Fe-CoMoO4 prepared in Example 1 for OER performance in a 1 M KOH environment is as Figure 6 shown. The S / Fe-CoMoO4 nanocomposite electrode only requires an overpotential of 202 mV to obtain a catalytic current of 100 mA cm -2 , and its overpotential is much lower than that of the prepared precursor S-CoMoO4 and Fe-CoMoO4 electrodes (337 mV, 370 mV).
[0054] The LSV curve of the electrocatalytic material S / Fe-CoMoO4 prepared in Example 1 for HER performance in a 1 M KOH environment is as Figure 7 shown. The S / Fe-CoMoO4 electrode exhibits an overpotential of 159 mV (100 mA cm -2 ), which is much lower than that of the precursor S-CoMoO4 and Fe-CoMoO4 electrodes (271 mV and 396 mV, respectively).
[0055] The long-term stability of the electrocatalytic material S / Fe-CoMoO4 prepared in Example 1 in a 1 M KOH environment is as Figure 8 shown. The fact that the performance shows almost no obvious downward trend under 5000 cv cycles indicates that the prepared material still has excellent stability under long-term test conditions.
[0056] In summary, the present invention uses a hydrothermal method, a self-sacrificial template and a tube furnace sulfidation method to prepare a bifunctional S / Fe-CoMoO4 electrocatalytic material. This catalyst is prepared by first introducing Fe into CoMoO4 through a self-sacrificial template on CoMoO4 nanoflowers and then performing sulfidation. The flower-like structure endows the catalyst with rich electrochemically active sites and enhanced mass diffusion kinetics. Thanks to the coupling effect of Fe and S co-doping, the synthesized S / Fe-CoMoO4 has good HER (42 mV @ 10 mA cm 3+ ) and OER (177 mV @ 10 mA cm -2 ) and -2) It has activity and good cycling performance, can be continuously applied for a long time, and will not cause secondary pollution to the environment during the application process. The preparation method of the present invention has low raw material cost, is easy to operate, is environmentally friendly and has the potential for large-scale production.
[0057] The descriptions and practices disclosed in the present invention are easy to think about and understand for those of ordinary skill in the art. Without departing from the principle of the present invention, several improvements and refinements can also be made. Therefore, the modifications or improvements made without deviating from the spirit of the present invention should also be regarded as within the protection scope of the present invention.
Claims
1. A method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material, characterized in that: The microstructure of the S / Fe-CoMoO4 electrocatalytic material is in the form of ultra-thin nanosheets attached to the surface of cobalt molybdate nanosheets, comprising the following steps: Step 1: Dissolve 1.4g-1.6g of Co(NO3)2·6H2O and 0.8g-0.9g of (NH4)6Mo7O in 25mL of distilled water. 24 ·4H2O aqueous solution, and at the same time, 1.1g-1.3g of CO(NH2)2 was added as a surfactant; the whole solution system was magnetically stirred for 30 minutes to form a uniform mixed solution; then, the mixed solution was transferred to a 50mL polytetrafluoroethylene-lined autoclave, and the treated nickel foam was immersed therein; Then the autoclave was sealed at 120 °C for 10 h, washed with deionized water and ethanol several times until neutral, and dried in vacuum to obtain CoMoO4 / NF; Step 2: Take out a piece of CoMoO4 / NF obtained in step 1 and transfer it to a 50 mL Teflon liner with K3[Fe(CN)6] aqueous solution, and carry out at 85°C for 2-3 hours; after cooling naturally to room temperature, take out the product, wash it with deionized water and ethanol several times until it is neutral, and vacuum dry it to obtain PBA / CoMoO4 / NF; Step 3: Place sulfur powder upstream of the PBA / CoMoO4 / NF obtained above, place it in a tube furnace, and after sulfurization under a nitrogen atmosphere, wash the nickel foam and dry it in a vacuum oven overnight to obtain S / Fe-CoMoO4.
2. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 1, the size of the nickel foam is (1-2) x (2-3) cm 2 The nickel foam should be placed in 50-100 ml of 2-4 mol / L HCl solution and ultrasonically treated for 5-15 minutes.
3. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 2, the concentration of K3[Fe(CN)6] aqueous solution is 4 mg mL -1 -12mg mL -1 .
4. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 3, the mass of sulfur powder is 0.5 to 3 g.
5. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 3, the vulcanization temperature is 300-450° C., the holding time is 1-3 hours, and the heating rate is 0.5-2° C. / min.
6. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 1, step 2 and step 3, washing is performed by using deionized water and ethanol for 3 to 5 times.
7. The method for preparing a bifunctional S / Fe-CoMoO4 electrocatalytic material according to claim 1, characterized in that: In step 1, step 2 and step 3, drying is carried out in a vacuum oven at a temperature of 50 to 80° C. for 6 to 12 hours.
8. Use of a bifunctional S / Fe-CoMoO4 electrocatalytic material prepared by the preparation method according to any one of claims 1 to 7 in hydrogen evolution reaction and oxygen evolution reaction.