Co-mno / cglm self-supporting electrocatalyst, preparation method and application thereof

Abstract

The application belongs to the technical field of electrocatalytic materials, and particularly relates to a Co-MnO / CGLM self-supporting electrocatalyst, a preparation method and application. Ganoderma wood is dispersed in a cobalt salt solution, a solvothermal reaction is carried out, then an organic ligand solution is added, stirring and standing are carried out to obtain ZIF-67 / GLM; a divalent manganese salt solution is added to the ZIF-67 / GLM, ion exchange is carried out with Co 2+ and Mn 2+ , Co-Mn / GLM is obtained; the Co-Mn / GLM is calcined under a protective atmosphere to obtain the Co-MnO / CGLM self-supporting electrocatalyst. The application combines ion exchange and pyrolysis, uses manganese oxide nanocubes as a structural framework, densely loads cobalt on the surface, forms a nanocube-shaped Co-MnO heterojunction catalyst, and anchors the catalyst on ganoderma wood, so that the prepared catalyst has excellent durability, and the current density remains basically unchanged during long-time operation.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalytic materials technology, specifically relating to a Co-MnO / CGLM self-supporting electrocatalyst, its preparation method, and its application. Background Technology

[0002] In the field of hydrogen production technology, electrocatalytic water splitting has become one of the most promising hydrogen generation pathways due to its environmental friendliness and sustainability. The core of this technology lies in developing high-performance bifunctional electrocatalysts capable of effectively driving the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Currently, although noble metal-based catalysts such as platinum / carbon (Pt / C) and ruthenium oxide (RuO2) exhibit excellent catalytic performance, their practical application is limited by the scarcity and high cost of these precious metals.

[0003] In recent years, breakthroughs have been made in transition metal-based water electrolysis electrocatalysts, with cobalt-based materials becoming a research hotspot due to their unique electronic properties. Compared to iron and nickel, cobalt's d-orbital energy distribution gives it a superior ability to regulate surface redox processes. In the OER process, the dynamically reconstructed amorphous active phase on the catalyst surface can precisely balance the adsorption strength and desorption rate of *OOH intermediates, thereby significantly improving reaction kinetics. However, this system still faces a dual challenge: on the one hand, high surface energy leads to the collapse of nanoparticle structures, causing continuous decay of active sites; on the other hand, single-component systems struggle to synergistically optimize the activation energy difference between the oxygen evolution reaction (OER) and the hydrogen reduction reaction (HER), severely limiting the overall energy conversion efficiency of the water splitting system. To address these challenges, heterojunction engineering has shown great potential. Its core mechanism lies in the charge redistribution at the heterojunction interface, where space charge regions drive directional electron migration, thereby forming an internal electric field. This electric field effect not only optimizes the local electronic density of states of active sites but also stabilizes the adsorption configuration of key intermediates through pd orbital hybridization. For example, Alsabban MM, Eswaran MK, Peramaiah K, et al. Unusual Activity of Rationally Designed Cobalt Phosphide / Oxide Heterostructure Composite for Hydrogen Production in Alkaline Medium[J].ACS nano, 2022(3):16.DOI:10.1021 / acsnano.1c09254, constructed CoP-CoxOy heterojunctions by CVD method, and electron transfer at the interface promoted water splitting kinetics. Professor Guo's team (Co / CoP Heterojunction on Hierarchically Ordered Porous Carbon as a Highly Efficient Electrocatalyst for Hydrogen and Oxygen Evolution[J]. Advanced Energy Materials, 2021.DOI:10.1002 / aenm.202102134.) optimized the adsorption energy and achieved electronic coupling at the interface by embedding Co / CoP heterojunctions into hierarchically porous carbon (HOMC). The integration of metal oxides provides a new dimension for heterojunction design. Their wide bandgap characteristics complement the metallic properties of cobalt, achieving efficient interfacial charge transport through Schottky contacts, while synergistically enhancing water dissociation and hydrogen proton reduction.

[0004] Therefore, integrating catalytic metal nanoparticles into highly conductive porous carbon matrices has become a promising approach to improve electrocatalytic performance. Although composites of synthetic carbon materials such as graphene and carbon nanotubes with metal nanoparticles have been extensively studied, their powder properties necessitate the use of binders for practical applications, which can hinder active sites and compromise long-term stability. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a Co-MnO / CGLM self-supporting electrocatalyst, its preparation method, and its applications. Through a strategy combining ion exchange and pyrolysis, a nanocube-shaped Co-MnO heterojunction catalyst is formed by densely loading cobalt onto the surface of manganese oxide nanocubes as the structural framework. This catalyst is anchored on graphitic carbonitride (g-C3N4) functionalized Ganoderma lucidum wood (CGLM). The Ganoderma lucidum wood retains its natural topological characteristics, forming a continuous conductive network that enhances electron transport and nanoparticle stability. The prepared catalyst exhibits excellent durability, with the current density remaining essentially constant during long-term operation.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions.

[0007] This invention provides a method for preparing a Co-MnO / CGLM self-supporting electrocatalyst, comprising the following steps:

[0008] S1. Ganoderma lucidum wood is dispersed in a cobalt salt solution and subjected to a solvothermal reaction to load cobalt ions onto the Ganoderma lucidum wood. Then, an organic ligand solution is added, and the mixture is stirred and allowed to stand to allow ZIF-67 nanocrystals to grow on the surface of the Ganoderma lucidum wood, thus obtaining ZIF-67 / GLM.

[0009] S2. Add a divalent manganese salt solution to ZIF-67 / GLM to make Co 2+ and Mn 2+ Ion exchange was performed to obtain Co-Mn / GLM.

[0010] S3. Under a protective atmosphere, Co-Mn / GLM is calcined, and Ganoderma lucidum wood is pyrolyzed to form a three-dimensional interconnected graphite network structure. MnO / Co cubic heterojunctions are formed on the three-dimensional interconnected graphite network structure to obtain a Co-MnO / CGLM self-supporting electrocatalyst.

[0011] Furthermore, the Ganoderma lucidum wood is made by removing the mycelium obtained from Ganoderma lucidum as the substrate. The ratio of cobalt used in the Ganoderma lucidum and cobalt salt solution is 2cm×2cm:5mmol. The cobalt salt solution is a methanol solution of cobalt nitrate hexahydrate.

[0012] Furthermore, the temperature of the solvothermal reaction is 80℃~150℃, and the time is 3h~5h.

[0013] Furthermore, the molar ratio of cobalt to organic ligand in the cobalt salt solution is 1:1 to 6, and the organic ligand solution is a methanol solution of 2-methylimidazole.

[0014] Furthermore, the mass ratio of divalent manganese salt to ZIF-67 / GLM in the divalent manganese salt solution is 1 to 1.7:1, and the divalent manganese salt solution is an anhydrous ethanol solution of manganese acetate tetrahydrate.

[0015] Furthermore, the specific conditions for ion exchange are a solvothermal reaction at 70℃~90℃ for 1h~2h.

[0016] Furthermore, the calcination temperature is 700℃~900℃, the calcination holding time is 2h~4h, the heating rate is 1℃ / min~3℃ / min, and the protective gas is nitrogen.

[0017] Furthermore, the preparation method of Ganoderma lucidum wood includes the following steps:

[0018] Add water to Ganoderma lucidum, heat to boiling and maintain for 0.5h to 1h, cool to room temperature and remove the substrate of Ganoderma lucidum, then dry to obtain Ganoderma lucidum wood.

[0019] This invention also provides a Co-MnO / CGLM self-supporting electrocatalyst, prepared using the above-described preparation method.

[0020] In addition, the present invention also provides the application of the above-mentioned Co-MnO / CGLM self-supporting electrocatalyst in the electrocatalytic splitting of water.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] This invention uses Ganoderma lucidum wood as a matrix and employs a solvothermal method to uniformly and densely grow ZIF-67 nanocrystals on the surface of the Ganoderma lucidum wood. The ZIF-67 nanocrystals exhibit a dodecahedral morphology. Then, partial Co is removed through ion exchange. 2+ Mn is reacted via ion exchange reaction 2+ Substitution, and finally during the calcination process, Mn 2+The process transforms the material into a MnO nanocubic framework, where Co migrates to the surface and is reduced to metallic Co nanoparticles. These Co nanoparticles are densely loaded onto the MnO nanocubic framework, forming a nano-Co / MnO cubic heterojunction catalyst. Simultaneously, the pyrolysis of Ganoderma lucidum wood forms a layered porous carbon structure, transforming it into a nitrogen-rich carbon framework, primarily containing graphitic carbonitrides and retaining a unique fibrous entanglement morphology. This provides anchoring points for the Co / MnO cubic particles, anchoring them onto the graphitic carbonitride-functionalized Ganoderma lucidum wood. The change in work function at the interface significantly enhances electron transfer, optimizes the electron density distribution of active sites, and adjusts the adsorption strength of reaction intermediates, effectively inhibiting the aggregation of Co / MnO. The Ganoderma lucidum wood retains its natural topological characteristics, forming a continuous conductive network that enhances electron transport and the stability of the nanoparticles.

[0023] The Co-MnO / CGLM self-supporting electrocatalyst provided by this invention exhibits excellent bifunctional electrocatalytic performance in alkaline electrolytes. The Co / MnO heterointerface promotes charge redistribution, synergistically optimizes the free energy of hydrogen adsorption, and reduces the OER energy barrier, demonstrating significant bifunctional activity at 10 mA·cm⁻¹. -2 At a current density of 10⁵ mV, the overpotential of HER is 10⁵ mV. At 50 mA·cm⁻¹ -2 At the specified current density, the overpotential of the OER is 250 mV. When used as both the anode and cathode in a complete moisture separation process, the electrolyzer requires only a minimum unit voltage of 1.61 V to achieve 50 mA·cm⁻¹. -2 The current density is [value missing]. Furthermore, the catalyst exhibited excellent performance in long-term durability tests. Attached Figure Description

[0024] Figure 1 This is a process flow diagram for preparing the Co-MnO / CGLM self-supporting electrocatalyst of this invention.

[0025] Figure 2 In Embodiment 2 of the present invention, GLM, ZIF-67 / GLM, and Co-Mn -2 / GLM and Co-MnO -2 Scanning electron microscope image of / CGLM. Figure 2 Figure a shows GLM, figure b shows ZIF-67 / GLM, and figure c shows Co-Mn. -2 / GLM, d figure is Co-MnO -2 / CGLM.

[0026] Figure 3 Co-MnO prepared in Examples 1 and 3 of this invention -2 Scanning electron microscope image of / CGLM Figure 3 (a) is Example 1, and (b) is Example 2.

[0027] Figure 4 Co-MnO prepared in Examples 4 and 5 of this invention -2 Scanning electron microscope image of / CGLM Figure 4 (a) is Example 4, and (b) is Example 5.

[0028] Figure 5 Co-MnO in Embodiment 2 of the present invention -2 Transmission topography of / CGLM. Figure 5 In the image, 'a' represents Co-MnO at 100 nm. -2 / CGLM transmission electron microscope image, b is the high-resolution transmission electron microscope image of the selected area in a, c is the electron diffraction pattern of the selected area in a, d is the Co-MnO at 500 nm -2 / CGLM transmission electron microscope image, d1 to d6 are the elemental mappings of C, N, O, S, Co and Mn in d, respectively.

[0029] Figure 6 Co-MnO in Embodiment 2 of the present invention -2 X-ray diffraction pattern of / CGLM.

[0030] Figure 7 Co-MnO in Embodiment 2 of the present invention -2 Raman spectra of / CGLM and comparative example 2Co / CGLM.

[0031] Figure 8 Co-MnO in Embodiment 2 of the present invention -2 XPS spectrum of / CGLM. Figure 8 In the image, (a) is the C 1s spectrum, (b) is the N 1s spectrum, (c) is the O 1s spectrum, (d) is the Co 2p spectrum, and (e) is the Mn 2p spectrum.

[0032] Figure 9 This is a band structure diagram of manganese oxide and Co before and after the heterojunction of the present invention. Figure 9 In the middle, (a) is before the heterojunction, and (b) is after the heterojunction.

[0033] Figure 10 The present invention relates to CGLM, Co / CGLM, and Co-MnO. -1 / CGLM, Co-MnO -2 / CGLM, Co-MnO -3 Oxygen reduction potential performance graphs for / CGLM and Ru2O. Figure 10 (a) represents the value at 5 mV·s −1(a) Under the condition of iR correction, the LSV polarization curve is shown; (b) is the polarization curve at 20 mA·cm. −2 and 50mA·cm −2 (c) OER overpotential measured at current density; (d) corresponding Tafel plot; (e) Nyquist plot; (f) Cdl value; (c) Co-MnO -2 Long-term stability of / CGLM after 50 hours at different current densities.

[0034] Figure 11 Example 2 of the present invention, Co-MnO -2 Structural characterization diagram of the / CGLM catalyst after OER testing. Figure 11 In the image, (a) is a scanning electron microscope image, (b) is an XRD pattern, (c) is a C 1s spectrum, (d) is an O 1s spectrum, (e) is a Mn 2p spectrum, and (f) is a Co 2p spectrum.

[0035] Figure 12 The present invention relates to CGLM, Co / CGLM, and Co-MnO. -1 / CGLM, Co-MnO -2 / CGLM and Co-MnO -3 Oxygen reduction potential performance graph of / CGLM. Figure 12 (a) at 5mV·s -1 (a) LSV polarization curves (after iR correction); (b) at 10 and 30 mA·cm −2 HER overpotential measured at current density; (c) corresponding Tafel plot; (d) Co-MnO -2 Long-term stability of / CGLM after 50 hours at different current densities.

[0036] Figure 13 Example 2 of the present invention, Co-MnO -2 / CGLM electrocatalytic water splitting performance diagram. Figure 13 (a) is the hydrolysis oxygen production diagram; (b) is the oxygen production at 5 mV·s. -1 Under the conditions of Co-MnO -2 / CGLM||Co-MnO -2 LSV curves for / CGLM and RuO2||Pt / C; (c) shows the curves at 10 mA·cm. -2 At current density, Co-MnO -2 / CGLM||Co-MnO -2 The it curves for / CGLM and RuO2||Pt / C.

[0037] Figure 14 Example 2 of the present invention, Co-MnO -2 / CGLM analysis diagram of the mechanism for improving OER and HER performance. Figure 14 In the middle (a), Co-MnO -2 (a) Optimization model of each step in the Co / CGLM oxygen anode process; (b) for Co / CGLM and Co-MnO -2 / CGLM model free energy diagram of oxygen anode process at U=0V; (c) is Co-MnO -2 The theoretical model of / CGLM; (d) is the Co / CGLM and Co-MnO after optimization by density functional theory (DFT). -2 / CGLM's hydrogen Gibbs free energy diagram. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that the technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods. The Ganoderma lucidum was collected from Boyang Town, Tongdao Dong Autonomous County, Huaihua City, Hunan Province.

[0040] Currently, integrating catalytic metal nanoparticles into highly conductive porous carbon matrices has become a promising method for improving electrocatalytic performance. Although composites of synthetic carbon materials, such as graphene and carbon nanotubes, with metal nanoparticles have been extensively studied, their powder properties necessitate the use of binders for practical applications. These binders can hinder active sites and compromise long-term stability. Therefore, the development of freestanding high-surface-area carbon substrates with abundant active sites has attracted considerable attention.

[0041] This invention leverages the unique layered porous structure of Ganoderma lucidum mycelium, which, through carbonization, can be transformed into a three-dimensional interconnected graphite network structure while retaining its unique fibrous entanglement morphology. This structure not only facilitates the uniform dispersion of metal nanoparticles but also effectively mitigates metal leaching and aggregation through carbon encapsulation. Based on this, a Co-MnO / CGLM heterostructure self-supporting electrocatalyst was successfully synthesized using a strategy combining ion exchange and pyrolysis. Details are as follows:

[0042] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0043] S1. Ganoderma lucidum wood (GLM) is dispersed in a cobalt salt solution and subjected to a solvothermal reaction to load cobalt ions onto the Ganoderma lucidum wood. Then, an organic ligand solution is added, and the mixture is stirred and allowed to stand to grow ZIF-67 nanocrystals on the surface of GLM, thus obtaining ZIF-67 / GLM.

[0044] S2. Add a divalent manganese salt solution to ZIF-67 / GLM to make Co 2+ and Mn 2+ Ion exchange was performed to obtain Co-Mn / GLM.

[0045] S3. Under a protective atmosphere, Co-Mn / GLM is calcined, and Ganoderma lucidum wood is pyrolyzed to form a three-dimensional interconnected graphite network structure. MnO / Co cubic heterojunctions are formed on the three-dimensional interconnected graphite network structure to obtain a Co-MnO / CGLM self-supporting electrocatalyst.

[0046] In this invention, such as Figure 1 As shown, ZIF-67 nanocrystals were uniformly and densely grown on the surface of Ganoderma lucidum (GLM) using a solvothermal method. The ZIF-67 nanocrystals exhibited a dodecahedral morphology. Then, partial Co removal was performed using ion exchange. 2+ Mn is reacted via ion exchange reaction 2+ Substitution, and finally during the calcination process, Mn 2+ The process transforms the material into a MnO nanocubic framework, where Co migrates to the surface and is reduced to metallic Co nanoparticles. These Co nanoparticles are densely loaded onto the MnO nanocubic framework, forming a nano-Co / MnO cubic heterojunction catalyst. Simultaneously, the pyrolysis of GLM forms a layered porous carbon structure, creating a nitrogen-rich carbon framework primarily composed of graphitic carbonitrides (g-C3N4) and retaining a unique fibrous entanglement morphology. This provides anchoring points for the Co / MnO cubic particles, anchoring them onto graphitic carbonitride (g-C3N4) functionalized Ganoderma lucidum wood (CGLM). The change in work function at the interface significantly enhances electron transfer, optimizes the electron density distribution of active sites, and adjusts the adsorption strength of reaction intermediates, effectively inhibiting the aggregation of Co / MnO. CGLM retains its natural topological characteristics, forming a continuous conductive network that enhances electron transport and nanoparticle stability.

[0047] In some embodiments, the *Ganoderma lucidum* wood is made from *Ganoderma lucidum* as a substrate, with mycelia obtained by removing the substrate. The ratio of cobalt used in the *Ganoderma lucidum* and cobalt salt solution is 2 cm × 2 cm: 5 mmol. The cobalt salt solution is a methanol solution of cobalt nitrate hexahydrate, a methanol solution of cobalt chloride, etc., the purpose of which is to form MOF. In a preferred embodiment of the present invention, the concentration of cobalt nitrate hexahydrate (Co(NO3)2·6H2O) in the methanol solution is 0.1 mmol / mL.

[0048] In some embodiments, the method for preparing Ganoderma lucidum wood includes the following steps:

[0049] After cutting the Ganoderma lucidum into pieces, add water, heat to boiling and maintain for 0.5h to 1h. After cooling to room temperature, scrape off the substrate of the Ganoderma lucidum with a knife, retain the original mycelium, and dry to obtain Ganoderma lucidum wood.

[0050] In some embodiments, the solvothermal reaction is carried out at a temperature of 80°C to 150°C for 3 to 5 hours. In this invention, after the solvothermal reaction is completed, the GLM is rinsed with deionized water to remove unreacted salts and impurities.

[0051] In some embodiments, the molar ratio of cobalt to organic ligand in the cobalt salt solution is 1:1 to 6. The organic ligand solution is a methanol solution of 2-methylimidazole. In a preferred embodiment of the present invention, the concentration of 2-methylimidazole in the methanol solution is 0.4 mmol / mL. After stirring at room temperature for 1 h, the mixture is allowed to stand for 12 h. The reaction product is then washed multiple times with methanol and vacuum dried to constant weight to obtain ZIF-67 / GLM.

[0052] In some embodiments, the mass ratio of divalent manganese salt to ZIF-67 / GLM in the divalent manganese salt solution is 1 to 1.7:1, and the divalent manganese salt solution is an anhydrous ethanol solution of manganese acetate tetrahydrate. In a preferred embodiment of the present invention, the concentration of manganese acetate tetrahydrate (MnC4H6O4·4H2O) in the anhydrous ethanol solution is 2 mg / mL to 3.4 mg / mL.

[0053] In some embodiments, the specific conditions for ion exchange are a solvothermal reaction at 70°C to 90°C for 1 to 2 hours. In this invention, after the solvothermal reaction is completed, the product is collected by centrifugation, thoroughly washed with deionized water, and vacuum dried at 60°C for 12 hours.

[0054] In some embodiments, the calcination temperature is 700℃~900℃, the calcination holding time is 2h~4h, the heating rate is 1℃ / min~3℃ / min, and the protective gas is nitrogen. In this invention, calcination involves Mn 2+The process transforms the material into a MnO nanocubic framework, where Co migrates to the surface and is reduced to metallic Co nanoparticles. These Co nanoparticles are densely loaded onto the MnO nanocubic framework, forming a nano-Co / MnO cubic heterojunction catalyst. On the other hand, Ganoderma lucidum wood undergoes carbonization to form a three-dimensional interconnected graphite network, creating a nitrogen-rich carbon framework that retains a unique fibrous entanglement morphology, providing anchoring points for the Co / MnO cubic particles.

[0055] This invention also provides a Co-MnO / CGLM self-supporting electrocatalyst, prepared using the above-described preparation method.

[0056] In addition, this invention also provides the application of the above-mentioned Co-MnO / CGLM self-supporting electrocatalyst in the electrocatalytic splitting of water. Using the Co-MnO / CGLM self-supporting electrocatalyst as the anode and cathode, and placing the cathode and anode in a 1M potassium hydroxide electrolyte, a two-electrode electrolyzer is assembled to perform electrocatalytic water splitting.

[0057] The Co-MnO / CGLM self-supporting electrocatalyst of this invention exhibits excellent bifunctional electrocatalytic performance in alkaline electrolytes. The Co / MnO heterointerface promotes charge redistribution, synergistically optimizes the free energy of hydrogen adsorption, and reduces the OER energy barrier, demonstrating significant bifunctional activity at 10 mA·m -2 At a current density of 10⁵ mV, the overpotential of HER is 10⁵ mV. At 50 mA·cm⁻¹ -2 At the specified current density, the overpotential of the OER is 250 mV. When used as both the anode and cathode in a complete moisture separation process, the electrolyzer requires only a minimum unit voltage of 1.61 V to achieve 50 mA·cm⁻¹. -2 The current density is [value missing]. Furthermore, the catalyst exhibited excellent performance in long-term durability tests.

[0058] The following specific examples will provide further explanation.

[0059] Example 1

[0060] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0061] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. The substrate was then dried to obtain Ganoderma lucidum wood (GLM). 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing, resulting in a cobalt nitrate solution. Ganoderma lucidum wood was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h using a solvothermal method. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0062] S2. Dissolve 100 mg of MnC4H6O4·4H2O in 50 mL of anhydrous ethanol and form a homogeneous solution under vigorous magnetic stirring. Then add 100 mg of ZIF-67 / GLM, stir for 15 min, and transfer to a 100 mL reaction vessel. Perform a solvothermal reaction at 80 °C for 1 h. After the reaction is complete, cool to room temperature, collect the product by centrifugation, wash thoroughly with deionized water, and vacuum dry at 60 °C for 12 h to obtain Co-Mn / GLM, named Co-Mn. -1 / GLM.

[0063] S3, Co-Mn -1 / GLM was placed in a tube furnace and heated to 800℃ at a rate of 3℃ / min under nitrogen atmosphere protection. After holding for 2 hours, it was naturally cooled to room temperature to obtain the Co-MnO / CGLM self-supporting electrocatalyst, named Co-Mn -1 / CGLM.

[0064] Example 2

[0065] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0066] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. Then, it was dried to obtain GLM. 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing to obtain a cobalt nitrate solution. Ganoderma lucidum was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h in a solvothermal manner. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0067] S2. Dissolve 135 mg of MnC4H6O4·4H2O in 50 mL of anhydrous ethanol and form a homogeneous solution under vigorous magnetic stirring. Then add 100 mg of ZIF-67 / GLM, stir for 15 min, and transfer to a 100 mL reaction vessel. Perform a solvothermal reaction at 80 °C for 1 h. After the reaction is complete, cool to room temperature, collect the product by centrifugation, wash thoroughly with deionized water, and vacuum dry at 60 °C for 12 h to obtain Co-Mn / GLM, named Co-Mn. -2 / GLM.

[0068] S3, Co-Mn -2 / GLM was placed in a tube furnace and heated to 800℃ at a rate of 3℃ / min under nitrogen atmosphere protection. After holding for 2 hours, it was naturally cooled to room temperature to obtain the Co-MnO / CGLM self-supporting electrocatalyst, named Co-Mn -2 / CGLM.

[0069] Example 3

[0070] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0071] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. Then, it was dried to obtain GLM. 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing to obtain a cobalt nitrate solution. Ganoderma lucidum was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h in a solvothermal manner. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0072] S2. 170 mg of MnC4H6O4·4H2O was dissolved in 50 mL of anhydrous ethanol and a homogeneous solution was formed under vigorous magnetic stirring. Then, 100 mg of ZIF-67 / GLM was added, and the mixture was stirred for 15 min. The solution was then transferred to a 100 mL reaction vessel and subjected to a solvothermal reaction at 80 °C for 1 h. After the reaction was completed, the mixture was cooled to room temperature, and the product was collected by centrifugation. The product was thoroughly washed with deionized water and then vacuum dried at 60 °C for 12 h to obtain Co-Mn / GLM, which was named Co-Mn. -3 / GLM.

[0073] S3, Co-Mn -3 / GLM was placed in a tube furnace and heated to 800℃ at a rate of 3℃ / min under nitrogen atmosphere protection. After holding for 2 hours, it was naturally cooled to room temperature to obtain the Co-MnO / CGLM self-supporting electrocatalyst, named Co-Mn -3 / CGLM.

[0074] Example 4

[0075] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0076] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. Then, it was dried to obtain GLM. 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing to obtain a cobalt nitrate solution. Ganoderma lucidum was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h in a solvothermal manner. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0077] S2. Dissolve 135 mg of MnC4H6O4·4H2O in 50 mL of anhydrous ethanol and form a homogeneous solution under vigorous magnetic stirring. Then add 100 mg of ZIF-67 / GLM, stir for 15 min, and transfer to a 100 mL reaction vessel. Perform a solvothermal reaction at 80 °C for 1 h. After the reaction is complete, cool to room temperature, collect the product by centrifugation, wash thoroughly with deionized water, and vacuum dry at 60 °C for 12 h to obtain Co-Mn / GLM, named Co-Mn. -2 / GLM.

[0078] S3, Co-Mn -2 / GLM was placed in a tube furnace and heated to 700℃ at a rate of 3℃ / min under nitrogen atmosphere protection. After holding for 2 hours, it was naturally cooled to room temperature to obtain the Co-MnO / CGLM self-supporting electrocatalyst.

[0079] Example 5

[0080] A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst includes the following steps:

[0081] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. Then, it was dried to obtain GLM. 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing to obtain a cobalt nitrate solution. Ganoderma lucidum was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h in a solvothermal manner. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0082] S2. Dissolve 135 mg of MnC4H6O4·4H2O in 50 mL of anhydrous ethanol and form a homogeneous solution under vigorous magnetic stirring. Then add 100 mg of ZIF-67 / GLM, stir for 15 min, and transfer to a 100 mL reaction vessel. Perform a solvothermal reaction at 80 °C for 1 h. After the reaction is complete, cool to room temperature, collect the product by centrifugation, wash thoroughly with deionized water, and vacuum dry at 60 °C for 12 h to obtain Co-Mn / GLM, named Co-Mn. -2 / GLM.

[0083] S3, Co-Mn -2 The CGLM was placed in a tube furnace and heated to 900°C at a rate of 3°C / min under a nitrogen atmosphere. After holding at this temperature for 2 hours, it was naturally cooled to room temperature to obtain the Co-MnO / CGLM self-supporting electrocatalyst, named Co-MnO. -2 / CGLM.

[0084] Comparative Example 1

[0085] A method for preparing a CGLM electrocatalyst includes the following steps:

[0086] S1. Cut Ganoderma lucidum into small pieces of 2cm×2cm, add an appropriate amount of deionized water, heat to boiling and maintain for 0.5h. After cooling to room temperature, scrape off the substrate of Ganoderma lucidum with a knife, retain the original mycelium, and then put it into drying to finally obtain GLM.

[0087] S3. Place GLM in a tube furnace and heat it to 800°C at a rate of 3°C / min under nitrogen atmosphere protection. After holding for 2 hours, allow it to cool naturally to room temperature to obtain the catalyst CGLM.

[0088] Comparative Example 2

[0089] A method for preparing a Co / CGLM electrocatalyst includes the following steps:

[0090] S1. Ganoderma lucidum was cut into 2cm × 2cm pieces, and an appropriate amount of deionized water was added. The mixture was heated to boiling and maintained for 0.5h. After cooling to room temperature, the substrate of Ganoderma lucidum was scraped off with a knife, retaining the original mycelium. Then, it was dried to obtain GLM. 5 mmol of Co(NO3)2·6H2O was dissolved in 50mL of methanol and stirred thoroughly to ensure uniform mixing to obtain a cobalt nitrate solution. Ganoderma lucidum was dispersed in the cobalt nitrate solution obtained above, and then transferred to a 100mL reaction vessel. The reaction was carried out at 120℃ for 4h in a solvothermal manner. After the reaction was completed, GLM was separated and washed with deionized water. 20 mmol of 2-methylimidazole was dissolved in 50mL of methanol and stirred thoroughly to form an organic ligand solution. The washed GLM was added to the organic ligand solution, stirred at room temperature for 1h, and allowed to stand for 12h. After standing, GLM was separated, washed multiple times with methanol, and dried under vacuum at 60℃ until completely dry to obtain ZIF-67 / GLM.

[0091] S3. Place ZIF-67 / GLM in a tube furnace and heat it to 800℃ at a rate of 3℃ / min under nitrogen atmosphere protection. After holding for 2 hours, allow it to cool naturally to room temperature to obtain the electrocatalyst Co / CGLM.

[0092] The electrocatalysts prepared in Examples 1 to 5 and Comparative Examples 1 to 2 were subjected to structural and performance tests, and the results are as follows.

[0093] Figure 2 In Embodiment 2 of the present invention, GLM, ZIF-67 / GLM, and Co-Mn -2 / GLM and Co-MnO -2 Scanning electron microscope image of / CGLM. Figure 2 Figure a shows GLM, figure b shows ZIF-67 / GLM, and figure c shows Co-Mn. -2 / GLM, d figure is Co-MnO -2 / CGLM. For example... Figure 2 As shown in Figure a, GLM exhibits disordered entanglement of hyphal fibers, forming a three-dimensional network with a multilayered porous structure. This unique structure promotes the growth of ZIF-67. Figure 2 Figure b illustrates the ZIF-67 / GLM composite structure, where GLM serves as the substrate, enabling the uniform and high-density growth of ZIF-67 nanocrystals on its surface. Figure 2 The magnified SEM image in the upper left corner of image b shows that the ZIF-67 particles exhibit a distinct dodecahedral morphology and are evenly distributed. Figure 2 As shown in c, after Mn 2+ After ion exchange and coprecipitation treatment, the nanoparticles transformed into a rough and irregular structure. For example... Figure 2 As shown in d, calcined Co-MnO -2 Morphological analysis of CGLM confirmed that uniformly dispersed cubic Co-MnO nanoparticles were formed on the surface of CGLM.

[0094] Figure 3 Co-MnO prepared in Examples 1 and 3 of this invention -2 Scanning electron microscope image of / CGLM Figure 3 In the examples, (a) is Example 1 and (b) is Example 2. Figure 3 and Figure 2 As shown, Mn 2+ The increased concentration enhanced the degree of ion substitution, resulting in more significant morphological reconstruction of nanoparticles.

[0095] Figure 4 Co-MnO prepared in Examples 4 and 5 of this invention -2 Scanning electron microscope image of / CGLM Figure 4 In the examples, (a) is Example 4 and (b) is Example 5. Figure 4 As shown, Co-MnO -2 / GLM nanoparticles exhibit subtle morphological changes upon calcination at different temperatures. At 700 °C, the nanoparticle size decreases, and morphological heterogeneity reduces. In contrast, calcination at 900 °C leads to significant particle coarsening and marked agglomeration. This phenomenon may be attributed to temperature-dependent atomic migration and diffusion kinetics.

[0096] Figure 5 Co-MnO in Embodiment 2 of the present invention -2 Transmission topography of / CGLM. Figure 5 In the image, 'a' represents Co-MnO at 100 nm. -2 / CGLM transmission electron microscope image, b is the high-resolution transmission electron microscope image of the selected area in a, c is the electron diffraction pattern of the selected area in a, d is the Co-MnO at 500 nm -2 / CGLM transmission electron microscope image, d1 to d6 are elemental mappings of C, N, O, S, Co and Mn in d, respectively. For example Figure 5 As shown in Figure a, Co-MnO -2 / CGLM crystal morphology, such as Figure 5As shown in Figure b, distinct lattice fringes with spacings of 0.256 nm and 0.204 nm were observed, corresponding to the (200) plane of manganese oxide and the (111) plane of metallic Co, respectively. This interfacial structure confirms the uniform growth of Co on the cubic surface of manganese oxide and the successful construction of the heterostructure. Furthermore, HR-TEM analysis revealed lattice fringes with a spacing of 0.336 nm, corresponding to the (002) plane of graphitic carbonitrides. The presence of nitrogen-rich carbon structures contributes to improving the structural stability and electrical conductivity of the material. Figure 5 As shown in Figure c, selected-area electron diffraction revealed clear diffraction rings, verifying the high crystallinity of the material. Figure 5 As shown in d1 to d6, the spatial distribution of the constituent elements is further clarified. Nitrogen doping from Ganoderma lucidum precursors optimizes the electronic structure of the carbon substrate, increases the density of active sites, and promotes electron transfer.

[0097] Figure 6 Co-MnO in Embodiment 2 of the present invention -2 X-ray diffraction pattern of / CGLM. (e.g.) Figure 6 As shown, the diffraction peaks at 51.8° and 60.6° correspond to the (111) and (200) crystal planes of cobalt. The diffraction peaks observed at 40.8°, 47.5°, 69.4°, 83.7°, and 88.4° correspond to the (111), (200), (220), (311), and (222) crystal planes of manganese oxide, respectively. Furthermore, the sample exhibits a significant diffraction peak at a 2θ angle of 30.9°, which corresponds to the (002) crystal plane of graphite (JCPDS: 87-1526). This indicates that CGLM is highly graphitized. The results show that the XRD pattern of the Co-MnO / CGLM composite exhibits three distinct diffraction peaks, corresponding to cobalt, manganese oxide, and g-C3N4, respectively.

[0098] Figure 7 Co-MnO in Embodiment 2 of the present invention -2 Raman spectra of / CGLM and the comparative example 2Co / CGLM. (See attached images.) Figure 7 As shown, at 1352cm -1 and 1595cm -1 Two distinct peaks were observed, corresponding to the D and G bands, respectively. Typically, the D band is mainly attributed to defects or disorder in the carbon framework, while the G band originates from a highly ordered graphite structure. After introducing manganese oxide and a certain amount of Co, I... D / I G The ratios were 0.970 and 0.937, respectively. These results indicate that the composite material has a high degree of graphitization and forms an effective electronic conduction network, significantly improving the conductivity of the catalyst.

[0099] Figure 8 Co-MnO in Embodiment 2 of the present invention -2 XPS spectrum of / CGLM. Figure 8 In the image, (a) is the C 1s spectrum, (b) is the N 1s spectrum, (c) is the O 1s spectrum, (d) is the Co 2p spectrum, and (e) is the Mn 2p spectrum. Figure 8 As shown, three distinct peaks can be identified in the C 1s spectrum, located at 284.6 eV (C=C) and 285.7 eV (CO). The N 1s spectrum shows three distinct peaks, located at 398.4 eV, 399.5 eV, 400.6 eV, and 402.1 eV, corresponding to pyridyl nitrogen, metallic nitrogen, pyrrolidinyl nitrogen, and graphitic nitrogen, respectively. Metallic nitrogen bonds significantly influence the electronic structure of the catalyst, thereby optimizing the adsorption energy of the reaction intermediates. Pyridyl nitrogen is generally considered a highly active doping site, while graphitic nitrogen enhances conductivity by modulating the electronic structure. In the O 1s spectrum, the peak at 529.2 eV is attributed to metal-oxygen bonding, while the peaks at 530.7 eV and 532.4 eV correspond to oxygen vacancies and absorbed oxygen species, respectively. In the Co 2p spectrum, four independent components are identified: Co-Co (i.e., CoO at 779.5 eV / 795.0 eV), Co-N (781.2 eV / 796.8 eV), Co-O (783.3 eV / 798.7 eV), and satellite peaks associated with Co 2p3 / 2 and Co 2p1 / 2 (786.6 eV / 802.1 eV). This coupling of weakly electronegative manganese oxide transforms Co nanoparticles into electron-rich active sites, thereby significantly enhancing their electrocatalytic performance. The Mn 2p spectrum shows the Mn... 2+ (640.6eV / 652.5eV), Mn 3+ The presence of a peak (642.7 eV) and a satellite peak (646.0 eV) indicates the presence of a Co-MnO4 atmosphere. -2 Mn exists simultaneously in the / CGLM system 2+ and Mn 3+ .

[0100] To investigate the charge transfer characteristics of Co-MnO heterostructures, this invention utilizes ultraviolet photoelectron spectroscopy (UPS) to accurately measure the working functions of Co and manganese oxide. Figure 9 This is a band structure diagram of manganese oxide and Co before and after the heterojunction of the present invention. Figure 9 In the diagram, (a) shows the area before the heterojunction, and (b) shows the area after the heterojunction. Here, EF represents the Fermi level, Evac represents the vacuum level, and Ev and Ec represent the potentials of the valence band and conduction band, respectively. Figure 9 As shown in (a), the figure of merit for manganese oxide is 7.063 eV, significantly higher than that for Co (3.153 eV), indicating that when the two phases are in contact, as... Figure 9As shown in (b), electrons migrate from Co, which has a lower figure of merit, to Manganese oxide, which has a higher figure of merit. This spontaneous electron transfer results in a space charge region at the Co-MnO interface: the Co side becomes positively charged due to electron loss, while the Manganese oxide side becomes negatively charged due to electron enrichment. This specific charge redistribution not only effectively modulates the adsorption free energy of the reaction intermediates but also promotes continuous charge transfer at the interface, significantly enhancing the catalytic activity of the material in HER and OER processes.

[0101] The electrocatalysts prepared in Examples 1 to 5 and Comparative Examples 1 to 2 were used for electrocatalytic water splitting.

[0102] Application of Co-MnO / CGLM self-supporting electrocatalyst in electrocatalytic water splitting. The Co-MnO / CGLM self-supporting electrocatalyst was used as both the anode and cathode. The anode and cathode were placed in a 1M potassium hydroxide electrolyte to assemble a two-electrode electrolyzer for electrocatalytic water splitting.

[0103] Figure 10 The present invention relates to CGLM, Co / CGLM, and Co-MnO. -1 / CGLM, Co-MnO -2 / CGLM, Co-MnO -3 Oxygen reduction potential performance graphs for / CGLM and Ru2O. Figure 10 (a) represents the value at 5 mV·s −1 (a) Under the condition of iR correction, the LSV polarization curve is shown; (b) is the polarization curve at 20 mA·cm. −2 and 50mA·cm −2 (c) OER overpotential measured at current density; (d) corresponding Tafel plot; (e) Nyquist plot; (f) Cdl value; (c) Co-MnO -2 The long-term stability of / CGLM after 50 hours at different current densities. For example... Figure 10 As shown in (a) and (b), Co-MnO -2 / CGLM exhibits superior OER catalytic activity compared to CGLM at high current densities (j 50 =593mV), Co / CGLM (j 50 =542mV), Co-MnO -1 / CGLM (j50=477mV), Co-MnO -3 / CGLM (j50=393mV) and RuO2 (j 50 =440mV). This is mainly reflected in its low overpotential (j =440mV). 50 =250mV). For example... Figure 10 As shown in (c), Co-MnO -2 / CGLM (73.8mV·dec) -1 The Tafel slope of ) is lower than that of CGLM (286.9 mV·dec). -1 ), Co / CGLM (264.5mV·dec) -1 ), Co-MnO -1 / CGLM (245.5mV·dec) -1 ), Co-MnO -3 / CGLM (175.2mV·dec) -1 ) and Ru2O (95.2mV·dec -1 This indicates that it possesses excellent intrinsic electrocatalytic activity. The rapid Faraday kinetics of Co-MnO-2 / CGLM are attributed to the introduction of manganese oxide, stemming from the synergistic enhancement of oxygen reduction reaction activity among manganese oxide, Co-O, and Co-N species. Figure 10 As shown in Figure (d), electrochemical impedance spectroscopy (EIS) analysis further validated the kinetic characteristics of the electrode / electrolyte interface. Co-MnO -2 The charge transfer resistance (Rct) of / CGLM is 0.40Ω, which is significantly lower than that of CGLM (5.98Ω), Co / CGLM (4.29Ω), and Co-MnO. -1 / CGLM (2.59Ω) and Co-MnO -3 / CGLM (0.86Ω), indicating that Co-MnO -2 / CGLM exhibits superior electron transport performance compared to other catalysts. For example... Figure 10 As shown in (f), at 10 mA·cm −2 At current density, Co-MnO -2 / CGLM exhibited significant stability over 16 hours with no noticeable performance degradation. Furthermore, when the current density increased to 100 mA·cm⁻¹, [the stability was improved]. −2 After being maintained for 18 hours, the catalyst recovered to 10 mA·cm⁻¹. −2 The catalyst remains stable even at high current densities. It exhibits rapid kinetics, with intense gas generation at high current densities. Due to the specific spatial confinement effect of the microchannels, the gas transport distance is shortened, bubble formation is accelerated, and the intense vibrations weaken the OH bond strength in the adsorbed water. Therefore, a large number of hydroxide ions are released into the alkaline medium, thus significantly improving the oxygen evolution efficiency at high current densities.

[0104] To more comprehensively analyze the number of intrinsic active sites, the roughness factor (RF), mass activity, and turnover frequency (TOF) were calculated, as shown in Table 1. The results show that Co-MnO -2 / CGLM has the highest turnover rate, reaching 0.0861s. -1This indicates that Co-MnO -2 / CGLM exhibits excellent intrinsic catalytic activity, further confirming its superior performance in the oxygen evolution reaction.

[0105] Table 1 Electrochemical results of the catalyst (η = 250 mV).

[0106]

[0107] Figure 11 Example 2 of the present invention, Co-MnO -2 Structural characterization diagram of the / CGLM catalyst after OER testing. Figure 11 In the image, (a) is a scanning electron microscope image, (b) is an XRD pattern, (c) is a C 1s spectrum, (d) is an O 1s spectrum, (e) is a Mn 2p spectrum, and (f) is a Co 2p spectrum. Figure 11 As shown in (a), Co-MnO -2 Metal ions in / CGLM undergo dissolution and redeposition during the OER process. This process can lead to changes in the active sites on the catalyst surface, resulting in a rougher or less uniform surface morphology. For example... Figure 11 As shown in (b), the diffraction peak intensity decreased after OER testing, but the phase composition remained essentially unchanged. Furthermore, the effects of OER testing on Co-MnO2 were systematically investigated using XPS. -2 The surface chemical state of / CGLM. For example... Figure 11 As shown in (c), a satellite peak appears at 292.8 eV in the high-resolution C 1s spectrum, attributed to π-electron transitions. Figure 11 As shown in (d), a significant increase in oxygen vacancies and absorbed oxygen species was observed in the O 1s spectrum. This is because surface reconstruction during the OER process leads to an increase in defects, with the increase in oxygen vacancies potentially enhancing the Co-MnO spectroscopy. -2 Key factors for / CGLM activity. For example... Figure 11 As shown in (e), after the OER test, Co-MnO -2 High-resolution Mn 2p spectra obtained by / CGLM show that the 2p³ / ² peak shifted positively by approximately 0.5 eV, indicating that Mn 2p peaks during the OER process are positively shifted. 2+ Partially oxidized to Mn 3+ This is consistent with the observation that higher Mn 3+ The content is related to enhanced OER activity because Mn 3+ It exhibits optimal Mn-oxygen interactions. For example... Figure 11 As shown in (f), after the OER test, the negative shift of the Co-N bond is mainly attributed to the partial Co... 2+ Oxidized to Co 3+ Co 3+The increase may be due to the formation of CoOOH, a substance that is highly active in the OER reaction.

[0108] Figure 12 The present invention relates to CGLM, Co / CGLM, and Co-MnO. -1 / CGLM, Co-MnO -2 / CGLM and Co-MnO -3 Oxygen reduction potential performance graph of / CGLM. Figure 12 (a) at 5mV·s -1 (a) LSV polarization curves (after iR correction); (b) at 10 and 30 mA·cm −2 HER overpotential measured at current density; (c) corresponding Tafel plot; (d) Co-MnO -2 Long-term stability of / CGLM after 50 hours at different current densities. Figure 12 As shown in Figure (a), the HER performance of Co-MnO / CGLM composites with different manganese oxide contents is compared. With the addition of an appropriate amount of manganese oxide, the HER activity is significantly improved. To achieve 100 mA·cm⁻¹... −2 The low current density requires an overpotential of 200 mV. Furthermore, compared to other non-commercial catalysts, these catalysts cannot achieve overpotentials exceeding 100 mA·cm⁻¹. −2 High current density. For example... Figure 12 As shown in (b), at 10 and 30 mA·cm −2 At the given current density, the overpotentials were 105 mV and 153 mV, respectively, indicating that the HER performance was optimal when the manganese oxide content was optimized.

[0109] like Figure 12 As shown in (c), the Tafel slope extracted from LSV data plays a crucial role in assessing reaction kinetics; in the absence of manganese oxide, the Tafel slope of the Co / CGLM catalyst reaches as high as 100.8 mV·dec. −1 When the manganese oxide content increases or decreases from the optimal level, the catalyst still exhibits a high Tafel slope: Co-MnO -1 / CGLM:119.1mV·dec −1 Co-MnO -3 / CGLM:114.1mV·dec −1 This indicates that the HER kinetics remain relatively slow. However, when an appropriate amount of manganese oxide is added, the Tafel slope decreases significantly to 48.8 mV·dec. −1 The Co-MnO4 composition was studied using it curves. -2 HER stability of / CGLM catalysts. Figure 12As shown in (d), at 100 mA·cm −2 At current density, Co-MnO -2 The / CGLM catalyst exhibited significant stability for 30 hours without a noticeable performance degradation. Furthermore, when the current density recovered to 10 mA·cm⁻¹... −2 Even at that time, the catalyst still maintained remarkable stability.

[0110] Using the Co-MnO / CGLM self-supporting electrocatalyst from Example 2 as both the anode and cathode, and assembling a two-electrode electrolyzer in a 1M potassium hydroxide electrolyte, water electrolysis was performed. During electrolysis, the electrolysis system was Co-MnO. -2 / CGLM||Co-MnO -2 / CGLM, with RuO2||Pt / C as a comparison. Electrocatalytic water splitting was performed at different current densities.

[0111] Figure 13 Example 2 of the present invention, Co-MnO -2 / CGLM electrocatalytic water splitting performance diagram. Figure 13 (a) is the hydrolysis oxygen production diagram; (b) is the oxygen production at 5 mV·s. -1 Under the conditions of Co-MnO -2 / CGLM||Co-MnO -2 LSV curves for / CGLM and RuO2||Pt / C; (c) shows the curves at 10 mA·cm. -2 At current density, Co-MnO -2 / CGLM||Co-MnO -2 The it curves for / CGLM and RuO2||Pt / C. (Example) Figure 13 As shown in Figure (a), a two-electrode electrolytic cell was constructed using Co-MnO4. -2 / CGLM was used as both anode and cathode to achieve oxygen production via hydrolysis (OWS) in a 1.0 M potassium hydroxide solution. Figure 13 As shown in (b), the assembled Co-MnO -2 / CGLM (+ / −) requires battery voltages of 1.61V and 1.72V to obtain 50mA·cm⁻¹ respectively. -2 and 100mA·cm -2 The current density. For example... Figure 13 As shown in (c), this is for a comprehensive evaluation of Co-MnO -2 The stability of / CGLM was tested using an IT curve for 50 hours. Throughout the test, Co-MnO -2 / CGLM exhibits excellent stability, with its current density remaining essentially stable over long periods of operation.

[0112] Figure 14 Example 2 of the present invention, Co-MnO -2 / CGLM analysis diagram of the mechanism for improving OER and HER performance. Figure 14 In the middle (a), Co-MnO -2 (a) Optimization model of each step in the Co / CGLM oxygen anode process; (b) for Co / CGLM and Co-MnO -2 / CGLM model free energy diagram of oxygen anode process at U=0V; (c) is Co-MnO -2 The theoretical model of / CGLM; (d) is the Co / CGLM and Co-MnO after optimization by density functional theory (DFT). -2 / CGLM's Gibbs free energy diagram for hydrogen. (Example) Figure 14 As shown in (a) and (c), in order to explore the internal mechanisms for improving OER and HER performance, Co-MnO4 was constructed and optimized. -2 The theoretical model of / CGLM. For example... Figure 14 As shown in Figure (b), the adsorption on Co / CGLM and Co-MnO is illustrated. -2 The free energy diagram of OER intermediates on the / CGLM oxidized surface. This indicates that in Co / CGLM and Co-MnO -2 In the OER reaction of / CGLM, the fourth fundamental stage (*OOH → *+O2) has the largest free energy change (ΔG4) and is the key step determining the reaction rate. Co-MnO -2 The ΔG4 of Co / CGLM is 1.69 eV, lower than that of Co / CGLM (2.28 eV). These results indicate that the Co-MnO4 concentration can be reduced by over-introducing manganese oxide to construct a heterojunction. -2 / CGLM reduces the reaction energy barrier in the OER process, thereby improving its OER performance.

[0113] At the same time, using DFT calculations, such as Figure 14 As shown in (d), Co / CGLM and Co-MnO were calculated. -2 The adsorption performance of / CGLM for hydrogen generation (H*). Compared with Co / CGLM (0.81 eV), Co-MnO -2 / CGLM (-0.15eV) shows the most favorable Gibbs free energy, indicating that Co-MnO -2 / CGLM is more conducive to water splitting to produce H2. These findings indicate that Co-MnO -2 The / CGLM structure has significant advantages in improving hydrogen generation efficiency. Therefore, adding an appropriate amount of manganese oxide can significantly improve the kinetics of H* adsorption and desorption during the catalytic process, thereby enhancing HER performance.

[0114] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0115] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for preparing a Co-MnO / CGLM self-supporting electrocatalyst, characterized in that, Includes the following steps: Ganoderma lucidum wood was dispersed in a cobalt salt solution and subjected to a solvothermal reaction to load cobalt ions onto the wood. Then, an organic ligand solution was added, and the mixture was stirred and allowed to stand to allow ZIF-67 nanocrystals to grow on the surface of the wood, resulting in ZIF-67 / GLM. The mycelium was obtained by removing the substrate from the Ganoderma lucidum wood. Add a divalent manganese salt solution to ZIF-67 / GLM to make Co 2+ and Mn 2+ Ion exchange was performed to obtain Co-Mn / GLM; The specific conditions for ion exchange are a solvothermal reaction at 70℃~90℃ for 1h~2h; Under a protective atmosphere, Co-Mn / GLM was calcined at a temperature of 700℃~900℃. The Ganoderma lucidum wood was pyrolyzed to form a three-dimensional interconnected graphite network structure, and MnO / Co cubic heterojunctions were formed on the three-dimensional interconnected graphite network structure to obtain a Co-MnO / CGLM self-supporting electrocatalyst.

2. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The ratio of cobalt used in the Ganoderma lucidum and cobalt salt solution was 2cm×2cm:5mmol, and the cobalt salt solution was a methanol solution of cobalt nitrate hexahydrate.

3. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The temperature of the solvothermal reaction is 80℃~150℃, and the time is 3h~5h.

4. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The molar ratio of cobalt to organic ligand in the cobalt salt solution is 1:1 to 6, and the organic ligand solution is a methanol solution of 2-methylimidazole.

5. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The mass ratio of divalent manganese salt to ZIF-67 / GLM in the divalent manganese salt solution is 1 to 1.7:

1. The divalent manganese salt solution is an anhydrous ethanol solution of manganese acetate tetrahydrate.

6. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The holding time for calcination is 2h to 4h, the heating rate is 1℃ / min to 3℃ / min, and the protective gas is nitrogen.

7. The method for preparing the Co-MnO / CGLM self-supporting electrocatalyst according to claim 1, characterized in that, The preparation method of Ganoderma lucidum wood includes the following steps: Add water to Ganoderma lucidum, heat to boiling and maintain for 0.5h to 1h, cool to room temperature and remove the substrate of Ganoderma lucidum to obtain mycelium, and dry to obtain Ganoderma lucidum wood.

8. A Co-MnO / CGLM self-supporting electrocatalyst, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 7.

9. The application of the Co-MnO / CGLM self-supporting electrocatalyst according to claim 8 in the electrocatalytic splitting of water.

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