A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalyst for hydrogen evolution based on bimetallic Mo / Fe-MOFs.

Abstract

The application belongs to the field of nanometer material preparation and energy, and discloses a preparation method of an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs derivation.(1) MoO3, FeCl3·6H2O and imidazole are dissolved in deionized water, and high-temperature condensation reflux is carried out for several hours to prepare a catalyst precursor bimetallic Mo / Fe-MOFs.(2) Deionized water and ethanol are used for cleaning, the product is collected by centrifugation and vacuum drying.(3) In a nitrogen environment, high-temperature calcination is carried out in a tube furnace at a certain heating rate for several hours to obtain an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs derivation. The catalyst regulates the electron cloud structure of the active site Mo through the push-pull electron effect between the bimetals, so that the hydrogen adsorption free energy is more close to 0eV. In addition, the catalyst has good conductivity and stability, and has certain light response capacity. Under the condition of photoelectric coupling, the catalyst can exhibit more superior hydrogen evolution activity, and has good application prospect.

Description

Technical Field

[0001] This invention relates to the field of photoelectrocatalytic material preparation, and more specifically, to a method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs, and the heterojunction electrocatalyst obtained therefrom, and its application in photoelectro-coupled hydrogen evolution reaction. Background Technology

[0002] Electrocatalytic hydrogen evolution (HER) technology is considered a key technology for solving the global energy crisis and environmental problems due to its ability to efficiently and stably generate hydrogen energy, which has high calorific value, zero carbon emissions, and is green and renewable. However, due to the large activation barrier of the H2O bond in water molecules, the reaction kinetics of HER are sluggish, and a very high overpotential is often required to achieve the hydrogen evolution reaction without a catalyst. Noble metal catalysts can drive the hydrogen evolution reaction at relatively low overpotentials, but their high cost and scarce reserves limit their large-scale application. Transition metal materials are considered a promising alternative due to their relatively superior catalytic properties and abundant reserves.

[0003] Transition metal catalysts have been extensively studied due to their unfilled d orbitals and tunable d band centers. Their outer electron cloud structure can be altered through modification or synergy with other elements, thereby adjusting their d band centers and achieving catalytic performance equivalent to or even superior to noble metal-based catalysts. While the preparation of bimetallic transition metal-based electrocatalysts is beneficial for improving HER performance, it is generally difficult to precisely introduce other metal elements into monometallic catalysts. Metal-Organic Frameworks (MOFs) are a class of porous materials composed of metal ions or clusters linked to organic ligands via coordination bonds. Due to their diverse ligands and high designability, researchers can easily and precisely design bimetallic or even multimetallic MOFs. More importantly, the monodisperse and uniformly distributed metal node structure of MOF materials facilitates the dispersion of active sites, avoiding the degradation of catalytic performance caused by active site aggregation.

[0004] Furthermore, current research on the synergistic mechanism of bimetallic catalysts and its regulation of d-band centers is limited, which severely restricts the selection of synergistic metal elements. Based on bimetallic π-symmetry (t... 2g The electronic push-pull effect between d-orbitals occurs when a bimetallic compound (M1, M2) forms an M1-O-M2 bond with oxygen (O). If M1 has more d-orbital electrons, the push-pull effect can be achieved through π-symmetry (t). 2gThe electron repulsion effect of d-orbitals transfers electrons from M1 to M2 via O. However, if M1 has fewer d-orbital electrons, this transfer can be achieved through π-symmetry (t). 2g The electron attraction effect of d-orbitals transfers electrons from M2 to M1 via O. Therefore, if we can use this strategy to select a suitable second metal to control the outer electrons of the first metal, we can achieve the goal of controlling its d-band center and improving its hydrogen evolution performance.

[0005] Among many transition metal catalysts, MoO2 exhibits good HER performance due to its high conductivity. However, because of the low electron cloud density on its active site Mo, its electrons interact with hydrogen atoms (H+). * The interaction between Fe and other elements is relatively weak, thus exhibiting poor HER performance. Iron is abundant in nature and inexpensive, making it a good candidate element for co-catalyzing Mo-based catalysts. Furthermore, Fe... 3+ The valence electron configuration is 3d 5 (t 2g 3 e g 2 ), Fe 2+ The valence electron configuration is 3d 6 (t 2g 4 e g 2 When it forms a Mo-O-Fe bond with Mo, due to the π-symmetry (t) between the Fe-O bonds... 2g The electron repulsion effect of d-orbitals causes more electrons to transfer to Mo, thereby enhancing its affinity for H. * The interaction between them.

[0006] For the reasons mentioned above, this invention introduces Fe into Mo-MOFs. 3+ A Mo-based electrocatalyst, Fe2Mo3O8 / C, with electron-rich active sites, was designed and prepared. Due to π-symmetry (t... 2g d-orbitals electron push-pull effect, Mo 4+ -O-Fe 2+ The Mo sites in the bond gain more electrons, and under photoelectric coupling conditions, when the current density reaches 10 mA / cm², 2 At this time, the overpotential of Fe2Mo3O8 / C is only -0.16V, exhibiting excellent photoelectric coupling catalytic hydrogen evolution performance. Summary of the Invention

[0007] [Technical Issues]

[0008] Gibbs adsorption free energy (ΔG) of molybdenum-based active sites in MoO2 H* The ΔG is relatively high, resulting in poor HER performance. Introducing a second metal in synergy with Mo can alter the electron cloud structure outside the Mo nucleus, thereby reducing its ΔG. H* This can improve the HER performance of bimetallic catalysts. However, there is currently limited research on the synergistic mechanism of bimetallic catalysts and the mechanism for regulating d-band centers, which seriously affects the selection of synergistic metal elements. In addition, the precise construction and design of bimetallic catalysts are quite difficult, and most catalyst active sites are clustered together, resulting in low utilization of active sites. The monodisperse and uniformly distributed metal node structure of MOF materials helps to solve the above problems.

[0009] [Technical Solution]

[0010] Therefore, this invention employs bimetallic π-symmetry(t) 2g )d-orbitals push-pull electron strategy, Mo formed through bimetallic Mo / Fe-MOFs 6+ -O-Fe 3+ The electron cloud structure of the active site Mo was successfully modulated by bonding. Subsequently, M was formed through calcination. 4+ -O-Fe 2+ The bonding further enhances the synergistic effect between the two metals, and the HER performance is significantly improved compared with the single transition metal Mo-based catalyst, providing a strategy for the design of bimetallic and multimetallic catalysts.

[0011] This invention is achieved by providing a method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs, comprising the following steps:

[0012] (1) Dissolve MoO3, FeCl3·6H2O and imidazole in deionized water, place them in a 250mL three-necked flask and reflux under high temperature for several hours to prepare bimetallic Mo / Fe-MOFs.

[0013] (2) The above catalyst precursor was washed with deionized water and ethanol, the product was collected by centrifugation, and dried in a vacuum drying oven at 60°C for 24 hours.

[0014] (3) The dried catalyst precursor was calcined at high temperature in a tube muffle furnace for several hours under nitrogen atmosphere at a certain heating rate to obtain an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs.

[0015] In this invention, a bimetallic π-symmetry (t) is employed. 2gThe d-orbitals push-pull electron strategy precisely constructed Mo-O-Fe bonds through Mo / Fe-MOFs, modulating the electron cloud density of the active Mo site and improving its photoresponse activity. Furthermore, calcination further enhanced the synergistic effect between the bimetals, improving the material's stability and endowing it with photoresponse capability. The prepared Fe2Mo3O8 / C exhibited photoresponse capability under photoelectric coupling conditions with a current density reaching 10 mA / cm². 2 The overpotential is only -0.16V.

[0016] Further, in step (1), the molar ratio of MoO3 to FeCl3·6H2O is 4:1 to 16:1, preferably 8:1; the molar ratio of the amount of imidazole added to the metal element in the solution is 1:0.5 to 1:1.5, preferably 1:1; the hydrothermal reaction is carried out at a constant temperature of 80 to 160°C for 10 to 48 hours, preferably at 130°C, and preferably for 24 hours.

[0017] Furthermore, in step (3), the atmosphere during the calcination process is nitrogen. By isolating oxygen, bimetallic Mo / Fe-MOFs can form an in-situ heterojunction Fe2Mo3O8 / C during the calcination process. Simultaneously, this allows for the formation of Fe... 3+ and Mo 6+ Reduction to form Mo 4+ -O-Fe 2+ Bonds are added to further enhance the synergistic effect of bimetals.

[0018] Further, in step (3), calcination is carried out in a tube furnace under a nitrogen atmosphere at a temperature of 600-800°C, preferably 700°C; the heating rate is 2-8°C / min, preferably 5°C / min; and the calcination time is 2-3 hours, preferably 2 hours.

[0019] An in-situ heterojunction Fe2Mo3O8 / C electrocatalyst for hydrogen evolution based on bimetallic Mo / Fe-MOFs was prepared using the method described above.

[0020] The advantages and positive effects of this invention are:

[0021] 1. Currently, there is limited research on the synergistic mechanism of bimetallic catalysts and its mechanism for regulating the d-band center, which severely limits the selection of synergistic metal elements. In this invention, bimetallic π-symmetry (t) is employed. 2g )d-orbitals push-pull electron strategy to construct Mo 6+ -O-Fe 3+ and Mo 4+ -O-Fe 2+This successfully increased the electron cloud density on the active site Mo, enhancing its affinity for H. * The interaction forces between the two metals enable Fe2Mo3O8 / C to exhibit good photoelectric coupling hydrogen evolution performance. This provides a new approach for the development of bimetallic and multimetallic materials and the selection of synergistic metals.

[0022] 2. In this invention, MOFs (Metal-Organic Facility Materials) are used as the substrate to construct a bimetallic catalyst. Due to the monodisperse and uniformly distributed metal node structure of MOFs, the introduction position of the second metal Fe can be precisely controlled, and the catalytic performance degradation caused by the aggregation of active sites can be avoided.

[0023] 3. In this invention, the synergistic effect between the bimetals is further enhanced by the reduction effect of the calcination process. During calcination, as the MOF framework decomposes, Fe... 3+ and Mo 6+ Reduced to Fe 2+ and Mo 4+ This further enhances the synergistic effect between the bimetals, greatly improves the conductivity and stability of the material, and gives the material photoresponsiveness. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some specific embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a scanning electron microscope image obtained according to Embodiment 1 of the present invention;

[0026] Figure 2 This is a scanning electron microscope image obtained according to Embodiment 2 of the present invention;

[0027] Figure 3 This is a scanning electron microscope image obtained according to Embodiment 3 of the present invention;

[0028] Figure 4 This is a scanning electron microscope image obtained according to Embodiment 4 of the present invention;

[0029] Figure 5 This is a scanning electron microscope image obtained according to Embodiment 5 of the present invention;

[0030] Figure 6 This is a scanning electron microscope image obtained according to Comparative Example 1 of the present invention;

[0031] Figure 7This is a scanning electron microscope image obtained according to Comparative Example 2 of the present invention;

[0032] Figure 8 This is a scanning electron microscope image obtained according to Comparative Example 3 of the present invention;

[0033] Figure 9 This is a scanning electron microscope image obtained according to Comparative Example 4 of the present invention;

[0034] Figure 10 This is a scanning electron microscope image obtained according to Comparative Example 5 of the present invention.

[0035] Figure 11 This invention is used to prove the π-symmetry (t) between Mo-O-Fe. 2g pDOS plot calculated by DFT (density functional theory) of the push-pull electron effect of d-orbitals.

[0036] Figure 12 This invention is used to prove the π-symmetry (t) between Mo-O-Fe. 2g XPS plot of the push-pull electron effect of d-orbitals.

[0037] Figure 13 This invention is used to prove the π-symmetry (t) between Mo-O-Fe. 2g )DFT (density functional theory) calculation of hydrogen adsorption free energy diagram based on the push-pull electron effect of d-orbitals. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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] Example 1

[0040] A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs includes the following steps:

[0041] (1) Dissolve 0.0256 mol MoO3, 0.0032 mol FeCl3·6H2O and 0.0290 mol imidazole in 200 mL of deionized water (the molar ratio of MoO3 and FeCl3·6H2O is 8:1), place in a 250 mL three-necked flask and reflux at 130 °C for 24 hours to obtain bimetallic Mo / Fe-MOFs;

[0042] (2) The above catalyst precursor was washed three times with deionized water and ethanol, the product was collected by centrifugation, and dried in a vacuum drying oven at 60°C for 24 hours.

[0043] (3) The dried catalyst precursor was calcined in a tube muffle furnace at 700°C for 2 hours under nitrogen atmosphere at a heating rate of 5°C / min to obtain an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst derived from bimetallic Mo / Fe-MOFs.

[0044] Example 2

[0045] A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs is different from that in Example 1 in that: in step (1), the amount of MoO3 added is 0.0272 mol, the amount of FeCl3·6H2O added is 0.0017 mol (the molar ratio of MoO3 and FeCl3·6H2O is 16:1), and the other conditions remain unchanged.

[0046] Example 3

[0047] A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs is different from that in Example 1 in that: in step (1), the amount of MoO3 added is 0.0232 mol, the amount of FeCl3·6H2O added is 0.0058 mol (the molar ratio of MoO3 and FeCl3·6H2O is 4:1), and the other conditions remain unchanged.

[0048] Example 4

[0049] A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs differs from Example 1 in that the calcination temperature selected in step (3) is 600℃, while the other conditions remain unchanged.

[0050] Example 5

[0051] A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs differs from Example 1 in that the calcination temperature selected in step (3) is 800℃, while the other conditions remain unchanged.

[0052] Comparative Example 1

[0053] The difference from Example 1 is that step (3) is not included.

[0054] Comparative Example 2

[0055] The difference from Example 2 is that step (3) is not included.

[0056] Comparative Example 3

[0057] The difference from Example 3 is that step (3) is not included.

[0058] Comparative Example 4

[0059] The difference from Example 1 is that in step (1), the amount of MoO3 added is 0.0290 mol, the amount of FeCl3·6H2O added is 0 mol, and the other conditions remain unchanged, so that MoO2 is obtained.

[0060] Comparative Example 5

[0061] The difference from Example 1 is that the amount of MoO3 added in step (1) is 0.0290 mol, the amount of FeCl3·6H2O added is 0 mol, and step (3) is not included, thus obtaining Mo-MOFs.

[0062] Performance Test Example 1

[0063] Hydrogen is highly anticipated in the energy and environmental fields due to its high calorific value, zero carbon emissions, and green renewability. However, there is almost no natural hydrogen energy on Earth, and most of it needs to be obtained through artificial synthesis. In this invention, a catalyst suspension was prepared by sonicating a synthesized catalyst (10 mg) in ethanol (480 μL) and Nafion (20 μL) solution for 1 hour. Then, 40 μL of the suspension was pipetted onto 0.5 × 0.5 cm carbon paper and dried at room temperature to form a film, which was then used to prepare the working electrode. A graphite rod and a saturated Ag / AgCl electrode were used as the counter electrode and reference electrode, respectively. The reversible hydrogen electrode (RHE) performance was tested using linear sweep voltammetry (LSV) on a Shanghai Chenhua CHI660e electrochemical workstation with a standard three-electrode system in an electrolyte solution with pH = 14. The reversible hydrogen electrode (RHE) was normalized and calibrated according to the equation E(RHE) = E(Ag / AgCl) + 0.222 + 0.0592 × pH. The tested current density was normalized based on the geometric surface area, and IR correction (E) was performed on all LSV curves. IR =E M -I×R S E IR It is the IR correction potential, E M It measures the potential, R S (This refers to ohmic resistance). The electrocatalysts prepared in Examples 1-5 and Comparative Examples 1-5 were subjected to HER performance tests using the above method. The test results are shown in Table 1.

[0064] Table 1. HER performance and characterization results of the catalyst.

[0065]

[0066] Among them, electrocatalytic overpotential OP 10 This indicates that under electrocatalytic conditions, when the current density reaches 10 mV / cm 2 The closer the overpotential required for the hydrogen evolution system is to zero, the better. The Tafel slope, calculated from the polarization curve (LSV), characterizes the HER reaction kinetics of the electrochemical catalyst; a smaller value indicates faster reaction kinetics. The electrochemical double-layer capacitance is directly proportional to the electrochemical active surface area of ​​the catalyst; a larger value indicates a larger electrochemical active surface area. The photoelectrocatalytic overpotential OP... 10 This indicates that under photoelectrocatalytic conditions, when the current density reaches 10 mV / cm 2 At that time, the closer the overpotential required by the hydrogen evolution system is to 0, the better.

[0067] As shown in Table 1, we can see that by introducing Fe into the Mo-MOFs synthesis process... 3+ The formed Mo 6+ -O-Fe 3+ The bond modulates the d-electron cloud structure of the active site Mo through the electronic push-pull effect between the bimetals. Therefore, compared with the Mo-MOFs of Comparative Example 5, the electrocatalytic overpotential OP of the bimetallic Mo / Fe-MOFs of Comparative Examples 1, 2, and 3 is higher. 10 and photocatalytic overpotential OP 10 Significantly reduced.

[0068] from Figure 6-8 , Figure 10 As shown in Table 1, Fe 3+ The introduction of [a specific substance] alters the coordination structure of Mo-MOFs, thus changing their morphology. Therefore, Comparative Examples 1, 2, and 3 show significant morphological changes compared to Comparative Example 5. Compared to single-metal Mo-MOFs (Comparative Example 5, [the morphology is different]). Figure 10 The rod-like structures of bimetallic Mo / Fe-MOFs differ from those of Fe. 3+ As the amount added increases, the structure gradually changes from an irregular sheet-like structure (Comparative Example 2). Figure 7 ) becomes a small granular structure (Comparative Example 1, Figure 6 Then, the small granular structure transforms into a larger spherical structure (Comparative Example 3). Figure 8 The morphology of the catalyst is closely related to the electrochemical double-layer capacitance. As shown in Table 1, compared with Comparative Examples 2, 3 and 5, the small particulate structure of Comparative Example 1 exhibits a larger double-layer capacitance, that is, its electrochemical active area is larger.

[0069] Comparative Examples 1-3 lack the calcination step (3) compared to Examples 1-3. Calcination under a nitrogen atmosphere can calcine Fe... 3+ and Mo 6+ Partial reduction, forming Mo 4+ -O-Fe 2+ The bond further enhances the synergistic effect between the bimetals, thereby further enhancing the HER performance of the active Mo site. Therefore, compared with Comparative Examples 1-3, the electrocatalytic overpotential OP of Examples 1-3 is significantly higher. 10 and photocatalytic overpotential OP 10 The conductivity and stability of the catalyst are significantly reduced. Furthermore, the calcination step greatly enhances the conductivity and stability of the catalyst.

[0070] Compared to Example 1, Examples 4 and 5 differed only in the temperature of calcination step (3). The Fe2Mo3O8 / C calcined at 600℃ (Example 4) and 800℃ (Example 5) showed decreased HER performance compared to Example 1. This is because excessively low temperatures lead to incomplete material formation and weaker bimetallic synergy, while excessively high calcination temperatures damage the material structure, resulting in decreased HER performance. Compared to Comparative Example 1, the performance of Examples 4 and 5 after high-temperature calcination was higher than that of the uncalcined Comparative Example 1, indicating that the calcination process significantly improves material performance.

[0071] Compared with Example 1, the HER performance of Mo sites in MoO2 obtained in Comparative Example 4 was very poor without the effect of bimetallic push-pull electrons, while Fe2Mo3O8 / C had more d orbital electrons in the Mo sites due to the push-pull electron effect between the bimetals, thus significantly improving the HER performance.

[0072] Furthermore, in order to further prove the bimetallic π-symmetry(t) 2g The correctness of the d-orbitals push-pull electron strategy was verified by performing DFT density functional theory calculations and XPS characterization on MoO2 and Fe2Mo3O8. Figure 11 The projected density of states (pDOS) plots of Mo d orbitals for MoO2 and Fe2Mo3O8 are shown (DFT calculations). It was found that compared to MoO2 (Mo-O-Mo), the d band center of Fe2Mo3O8 (Mo-O-Fe) is significantly lower. This lower d band center implies an increase in the number of electrons in the Mo d orbitals. This result is consistent with our π-symmetry (t... 2g This aligns with the push-pull electron effect of d-orbitals. For example... Figure 12High-resolution Mo3d XPS spectra of MoO2 and Fe2Mo3O8 show that, compared to MoO2, the Mo 3d binding energy sites in Fe2Mo3O8 shift to lower binding energy positions. This shift in XPS binding energy sites to lower binding energy positions indicates that Mo has gained electrons, further proving the correctness of our strategy. Figure 13 The hydrogen adsorption free energy diagrams of Mo sites in MoO2 and Fe2Mo3O8 are shown (DFT calculations). It was found that the hydrogen adsorption free energy of Mo sites in Fe2Mo3O8 (0.54 eV) is significantly lower than that in MoO2 (1.20 eV), indicating that its Mo sites possess more electrons and are more compatible with H. * The interaction is stronger. Therefore, the hydrogen evolution performance, characterization, and DFT calculation results of the material all confirm the bimetallic π-symmetry(t) 2g The correctness of the d-orbitals push-pull electron strategy.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing an in-situ heterojunction Fe2Mo3O8 / C electrocatalyst for hydrogen evolution based on bimetallic Mo / Fe-MOFs, characterized in that, Includes the following steps: (1) MoO3, FeCl3·6H2O and imidazole are dissolved in deionized water. The molar ratio of MoO3 to FeCl3·6H2O is 4:1 to 16:

1. The ratio of the amount of imidazole added to the total molar sum of moles of molybdenum and iron in the solution is 1:1 to 1:1.

5. The mixed solution is then placed in a 250 mL three-necked flask and refluxed for 24 to 48 hours to prepare bimetallic Mo / Fe-MOFs. The hydrothermal reaction temperature of the reflux is 80 to 160 °C. (2) The above catalyst precursor was washed with deionized water and ethanol, the product was collected by centrifugation, and dried in a vacuum drying oven at 60°C for 24 hours. (3) The dried catalyst precursor was calcined at high temperature in a tube muffle furnace for several hours under nitrogen atmosphere at a certain heating rate to obtain an in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst based on bimetallic Mo / Fe-MOFs.

2. The method for preparing the in-situ heterojunction Fe2Mo3O8 / C electrocatalyst for hydrogen evolution based on bimetallic Mo / Fe-MOFs according to claim 1, characterized in that, In step (3), the heating rate of the tube muffle furnace in nitrogen atmosphere is 2-8℃ / min, the calcination temperature is 600-800℃, and the calcination time is 2 hours.

3. A bimetallic Mo / Fe-MOFs-derived in-situ heterojunction Fe2Mo3O8 / C electrocatalytic hydrogen evolution catalyst prepared by the preparation method according to any one of claims 1-2.

Images