Phosphorus-doped double-vacancy heterostructure material, preparation method and application
By constructing a phosphorus-doped MoS2/MoO2 heterostructure on carbon cloth, the problems of slow kinetics and poor stability of MoS2 catalyst in water electrolysis were solved, achieving efficient and stable water electrolysis catalytic performance and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JILIN NORMAL UNIV
- Filing Date
- 2025-12-09
- Publication Date
- 2026-04-14
AI Technical Summary
Existing MoS2 catalysts exhibit slow HER and OER kinetics in water electrolysis, and are costly and unstable, making it difficult to simultaneously and efficiently catalyze both processes. Traditional methods also result in uneven distribution of active sites, affecting catalytic efficiency.
Phosphorus-doped MoS2/MoO2 heterostructures were constructed on carbon cloth substrates. A composite nanostructure rich in sulfur and oxygen vacancies was formed by hydrothermal method and heat treatment. Polyacids were used as precursors to achieve uniform doping and sulfidation, forming a heterostructure interface with strong electronic interactions.
The catalyst's HER and OER performance under acidic conditions has been improved, overcoming the bottlenecks in activity, stability, and cost, and achieving efficient and stable water electrolysis catalysis, which is superior to existing non-precious metal catalysts.
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Figure CN121853007A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of electrocatalysis technology, specifically a phosphorus-doped double-vacancy heterostructure material, its preparation method, and its application. Background Technology
[0002] Hydrogen (H2) energy, as a clean, efficient, and low-carbon energy source, is considered a key pathway to achieving carbon neutrality. Water electrolysis for hydrogen production converts renewable electricity into high-purity hydrogen, making it one of the most promising methods for large-scale "green hydrogen" production. However, the kinetics of the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode in this technology are slow, both requiring high energy consumption. Therefore, highly efficient electrocatalysts are urgently needed to reduce energy consumption and improve efficiency. Currently, noble metal-based materials (such as Pt, RuO2, and IrO2) are considered benchmark electrocatalysts for HER and OER, but their scarce reserves and high costs limit their large-scale application. Furthermore, single noble metal-based materials are difficult to efficiently catalyze both HER and OER simultaneously and exhibit poor stability. Therefore, developing cost-effective, efficient, and durable bifunctional electrocatalysts is of great significance to the water electrolysis for hydrogen production industry.
[0003] In recent years, molybdenum disulfide (MoS2) has attracted considerable attention in the field of electrocatalytic HER due to its low cost, good catalytic activity, and stability. However, the layered structure of MoS2 is catalytically inert, with active sites located only at the edges of its lamellae, resulting in relatively low inherent activity. Furthermore, its poor in-plane conductivity affects electron transfer to active sites, thus significantly limiting its practical application. Additionally, when using traditional metal salts (such as ammonium molybdate) as raw materials to prepare MoS2 catalysts, the uneven composition during sulfidation can lead to uncontrollable distribution of active sites, resulting in reduced catalytic efficiency and compromised stability. Currently, although methods such as chemical doping, defect engineering, and heterostructure construction can effectively enhance the intrinsic HER activity of MoS2, the anionic S... 2- Because inactive cations have a weaker adsorption effect on oxygen-containing intermediates, MoS2 is rarely used as an OER catalyst. Summary of the Invention
[0004] Against this backdrop, incorporating functional components with OER activity (such as Mo-based oxides) into the MoS2 system to construct heterostructure catalysts has become a cutting-edge design trend in next-generation catalytic materials. By precisely constructing heterostructure interfaces and controlling defect concentrations, not only can more active sites be provided for the reaction, but the adsorption / desorption behavior of reaction intermediates can also be optimized and the reaction energy barrier lowered through electronic synergistic effects, potentially becoming a highly efficient bifunctional catalytic active center. Therefore, developing a MoS2 / MoO2 heterostructure catalyst directly anchored on a carbon cloth substrate with abundant dual vacancies can not only create high-performance catalytic active sites but also achieve "integrated" catalyst-electrode integration, eliminating interfacial resistance. This provides core materials for next-generation efficient, stable, and low-cost water electrolysis technology, and has significant scientific implications for realizing a hydrogen economy.
[0005] The technical solution of the present invention is as follows: a phosphorus-doped double-vacancy heterostructure material, comprising: a conductive substrate and a composite nanostructure grown on the conductive substrate; the composite nanostructure comprises a phosphorus-doped molybdenum disulfide phase containing sulfur vacancies and a molybdenum dioxide phase containing oxygen vacancies, wherein the molybdenum disulfide phase and the molybdenum dioxide phase are in situ composited to form a heterostructure.
[0006] Furthermore, the conductive substrate is one of carbon cloth, carbon paper, nickel foam, or metal foil.
[0007] Furthermore, the composite nanostructure is an array of nanosheets grown in a vertically intersecting manner.
[0008] Furthermore, the X-ray diffraction pattern of the material shows diffraction peaks belonging to both molybdenum disulfide and molybdenum dioxide.
[0009] A method for preparing phosphorus-doped double-vacancy heterostructure materials includes the following steps: S1. Provide a precursor solution containing molybdenum source, phosphorus source and sulfur source, and grow phosphorus-doped P-MoS2 rich in sulfur vacancies on a pretreated conductive substrate by hydrothermal method. S2. Under an inert or reducing atmosphere, the conductive substrate loaded with P-MoS2 obtained in step S1 is heat-treated to convert some of the P-MoS2 into MoO2 rich in oxygen vacancies in situ, thereby forming a P-MoS2 / MoO2 heterostructure.
[0010] Furthermore, in step S1, the molybdenum source and phosphorus source are phosphomolybdic heteropolyacids or their salts.
[0011] Furthermore, the phosphomolybdic heteropolyacid is (NH4)6[P2Mo 18 O 62 ]·14H2O.
[0012] Furthermore, in step S1, the hydrothermal reaction temperature is 180-220℃ and the reaction time is 18-30 hours; in step S2, the heat treatment temperature is 350-450℃ and the time is 2-4 hours.
[0013] Application of a phosphorus-doped double-vacancy heterostructure material in a water electrolysis hydrogen production device.
[0014] Furthermore, the material is used as a catalyst for the cathode hydrogen evolution reaction or the anode oxygen evolution reaction in water electrolysis.
[0015] The beneficial effects of this invention are as follows: 1. The heterostructured water electrolysis catalyst of the present invention is prepared using polyacids as precursors. Its well-defined molecular structure and good solubility can provide a uniform spatial atomic arrangement and ensure sufficient contact with the sulfur source, achieving uniform doping and sulfidation at the single-molecule level.
[0016] 2. In the heterostructure water electrolysis catalyst of the present invention, the strong electronic interaction between the P-MoS2 phase and the MoO2 phase, as well as the sulfur vacancies and oxygen vacancies formed in situ, can effectively regulate the electronic structure of the catalyst, improve the HER, OER and total water electrolysis performance of the P-MoS2 / MoO2 heterostructure under acidic conditions, and outperform most non-precious metal catalysts currently reported.
[0017] 3. This invention simultaneously overcomes the bottlenecks of activity, stability, and cost in water electrolysis, providing a novel approach to the synthesis of catalysts and electrocatalysts for water electrolysis. Attached Figure Description
[0018] Figure 1 The images show the XRD patterns of the catalysts obtained in Example 1 and Comparative Examples 1-2.
[0019] Figure 2 This is a transmission electron microscope image of Example 1.
[0020] Figure 3 The X-ray photoelectron spectra of Example 1, Comparative Example 1, and Comparative Example 2 are shown.
[0021] Figure 4 This is a comparison of the HER polarization curves of Example 1, Comparative Examples 1-2, and commercial Pt / C in 0.5 M H2SO4 electrolyte.
[0022] Figure 5 This is a comparison of the Tafel slope of hydrogen evolution in Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte.
[0023] Figure 6 This is a comparison of the OER polarization curves of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte.
[0024] Figure 7 This is a comparison of the oxygen evolution Tafel slopes of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte.
[0025] Figure 8 The electrochemical impedance spectroscopy spectra of Examples 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte are shown.
[0026] Figure 9 This is a comparison of the total water electrolysis polarization curves of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte.
[0027] Figure 10 The chronocurrent response diagram for Example 1 in 0.5 M H2SO4 electrolyte is shown.
[0028] Figure 11 This is a scanning electron microscope image after the stability test of Example 1.
[0029] Figure 12 The image shows the XRD pattern after the stability test in Example 1.
[0030] Figure 13 This is a comparison chart of the voltages of Example 1 and existing products in a water-splitting battery in 0.5 M H2SO4 electrolyte.
[0031] Figure 14 This is the Faraday efficiency diagram for Example 1. Detailed Implementation
[0032] To address the shortcomings of existing technologies and the needs of research and application in this field, one objective of this invention is to provide a dual-vacancy heterostructure water electrolysis catalyst. The catalyst is characterized by using carbon cloth as a substrate, and its heterostructure consists of a phosphorus-doped, sulfur-vacancy-rich MoS2 phase and an oxygen-vacancy-rich MoO2 phase. The phosphorus-doped, sulfur-vacancy-rich MoS2 phase in the electrocatalyst is generated using polyacids as precursors, while the oxygen-vacancy-rich MoO2 phase is generated through thermal conversion induction. This electrocatalyst exhibits excellent catalytic performance in acidic water electrolysis; the electrocatalyst is designated P-MoS2 / MoO2.
[0033] The preparation method of the phosphorus-doped dual-vacancy heterostructure water electrolysis catalyst P-MoS2 / MoO2 of the present invention is carried out according to the following steps: Step 1: (NH4)6[P2Mo 18 O 62 ]·14H2O (P2Mo 18 Preparation of ) First, 10.0 g of sodium molybdate was dissolved in 45 mL of deionized water to form a clear solution. Then, 1.5 mL of phosphoric acid and 8 mL of concentrated hydrochloric acid were added dropwise under vigorous stirring. The mixture was heated at 110 °C for 8 h. After cooling to room temperature, 10.0 g of ammonium chloride was added to the reaction solution. The resulting yellow precipitate was separated by filtration and dried in a vacuum oven at 70 °C for 12 h to obtain the precursor, P2Mo. 18 .
[0034] Step 2: Preparation of P-MoS2 Take a piece with dimensions of 2×2 cm 2 The carbon cloth was first soaked in a mixed solution of concentrated nitric acid and concentrated sulfuric acid (volume ratio 1:3) for 6 hours, and then washed with deionized water until the solution was neutral. 0.38 g of P2Mo was then added. 18 0.36 g of thiourea was dissolved in 70 mL of deionized water and stirred at room temperature for 30 min. The mixture and the treated carbon cloth were then transferred to a 50 mL polytetrafluoroethylene autoclave and hydrothermally reacted at 200 °C for 24 h. After naturally cooling to room temperature, the mixture was washed with deionized water and dried at 70 °C for 12 h to obtain P-MoS2.
[0035] Step 3: Preparation of P-MoS2 / MoO2 The prepared P-MoS2 was placed in a tube furnace and heat-treated at 400 °C for 3 h in an argon atmosphere. After cooling, no further treatment was required to obtain the P-MoS2 / MoO2 heterostructure electrocatalyst.
[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this does not limit the present invention in any way. Example
[0037] The preparation method and application of the P-MoS2 / MoO2 heterostructure catalyst provided in Example 1 are as follows: 10.0 g of sodium molybdate was dissolved in 45 mL of deionized water to form a clear solution. 1.5 mL of phosphoric acid and 8 mL of concentrated hydrochloric acid were added with stirring at room temperature. The mixture was heated at 110 °C for 8 h. After cooling to room temperature, 10.0 g of ammonium chloride was added to the reaction solution. The yellow precipitate was separated by filtration and dried in a vacuum oven at 70 °C for 12 h to obtain the polyacid precursor P2Mo. 18 ; Take a 2×2 cm piece 2 The carbon cloth was soaked in a mixed solution of concentrated nitric acid and concentrated sulfuric acid (volume ratio 1:3) for 6 hours, then washed with deionized water until the solution was neutral to remove any possible oxides and organic impurities on the surface, and then dried in an oven at 70°C for 12 hours for later use. 0.38 g P2Mo 18 0.36 g of thiourea was added to 70 mL of deionized water and stirred at room temperature for 30 min to ensure complete dissolution of all components. The mixture was then transferred to a polytetrafluoroethylene (PTFE) reactor liner, and treated carbon cloth was added. The mixture was then hydrothermally reacted at 200 °C for 24 h. After the reaction, the mixture was cooled to room temperature, washed with deionized water, and dried in a 70 °C oven for 12 h to obtain P-MoS2. The obtained P-MoS2 was placed in a tube furnace and heat-treated at 400 °C for 3 h in an argon atmosphere. After cooling to room temperature, the sample was recovered to obtain the P-MoS2 / MoO2 heterostructure electrocatalyst.
[0038] Comparative Example 1: The difference between Comparative Example 1 and Example 1 is that, under the premise of using the same process, heat treatment was excluded to obtain P-MoS2.
[0039] Comparative Example 2: The difference between Comparative Example 2 and Example 1 is that, under the premise of using the same process, heat treatment was excluded, and ammonium molybdate was used instead of P2Mo. 18 MoS2 was obtained by using it as a molybdenum source.
[0040] Experimental Example 1: Examples 1 and Comparative Examples 1-2 were used as catalysts in 0.5 M H₂SO₄ electrolyte for HER, OER, and total water splitting tests. Electrochemical tests were performed on a 1470E / 1455 multichannel electrochemical workstation using a standard three-electrode system: Examples 1-3 and Comparative Examples 1-2 were the working electrodes, the Ag / AgCl electrode was the reference electrode, and the Pt mesh was the counter electrode. Linear sweep voltammetry (LSV) curves were plotted at 2 mV s⁻¹. -1 The scanning rate was measured.
[0041] Figure 1The XRD patterns of the catalysts obtained in Example 1 and Comparative Examples 1-2 are shown. As shown, the characteristic peaks of MoS2 and P-MoS2 match well with the standard card (JCPDS no. 137-1429). Compared with MoS2, the diffraction peak intensity of P-MoS2 gradually decreases. This is because during the doping process, some S sites are occupied by P atoms, which disrupts the lattice balance, causing adjacent S atoms to detach from the lattice and form sulfur vacancies, significantly reducing the crystallinity of the catalyst. After heat treatment, P-MoS2 shows some new diffraction peaks at approximately 26°, 37°, and 53°, corresponding to the MoO2 phase. With the extension of heat treatment time, the intensity of the diffraction peaks corresponding to the MoO2 phase gradually increases. This is because during the heat treatment process, MoS2 is oxidized in situ, forming a P-MoS2 / MoO2 heterostructure composite material. After heat treatment, the diffraction peaks corresponding to the (002), (101) and (110) crystal planes of MoS2 became sharp again, while the diffraction peaks corresponding to the (103) crystal plane were clearly visible. This is due to the recovery of some S vacancies during the heat treatment process.
[0042] Figure 2 The image shows a transmission electron microscope (TEM) image of Example 1. As can be seen from the image, P-MoS2 / MoO2 exhibits a nanosheet structure, from which two different types of lattice fringes and abundant heterostructure interfaces can be clearly observed. The interplanar spacings of 0.62 nm and 0.24 nm correspond to the (002) crystal plane of MoS2 and the (202) crystal plane of MoO2, respectively. Furthermore, some lattice fringes are discontinuous, indicating the presence of a defect-rich structure.
[0043] Figure 3 The X-ray photoelectron spectra of Example 1, Comparative Example 1, and Comparative Example 2 are shown. The characteristic peaks of the Mo 3d spectrum of MoS2 at 229.4 and 232.7 eV correspond to Mo 4+ Mo 3d 5 / 2 and Mo 3d 3 / 2 The two characteristic peaks at 228.2 and 231.5 eV correspond to uncoordinated Mo associated with S vacancies. Compared to MoS2, the characteristic peaks of P-MoS2 shift towards higher binding energies, indicating that the introduction of P dopant can modulate the electronic structure around Mo sites. After heat treatment, the characteristic peaks of P-MoS2 / MoO2 shift further compared to P-MoS2, indicating that the electronic structure of MoS2 can be further modulated by the formation of MoS2 / MoO2 heterostructures. From the integrated area perspective, the content of uncoordinated Mo in both P-MoS2 and P-MoS2 / MoO2 increases significantly, indicating that P doping and the formation of heterostructures increase vacancies. In the S 2p spectrum of MoS2, the characteristic peaks at 162.3 and 163.4 eV correspond to the terminal S1 of the MoS2 crystalline phase. 2-The characteristic peaks at 163.7 and 164.9 eV correspond to the bridged amorphous MoS₂ state. x Phase S2 2- State. Compared to MoS2, the S content in P-MoS2 and P-MoS2 / MoO2 is higher. 2- The characteristic peak positions of S2 underwent a positive shift, indicating the presence of electron transfer and interaction. XPS results show that the introduction of P dopant bridges S2. 2- The concentration of P increases, but after heat treatment, its concentration decreases significantly. This is because P atoms occupy some S sites during the doping process, and subsequently bridge with adjacent S atoms to create S vacancies and bridged S2 sites. 2- The uncoordinated Mo atoms then return to their initial positions after heat treatment to achieve a stable state. Therefore, the increased number of uncoordinated Mo atoms in P-MoS2 / MoO2 may be due to the formation of oxygen vacancies in the P-MoS2 / MoO2 heterostructure. The O 1s spectrum of P-MoS2 / MoO2 shows three characteristic peaks, corresponding to lattice oxygen, defect oxygen, and surface adsorbed oxygen, respectively, confirming the presence of oxygen vacancies in the heterostructure catalyst.
[0044] Figure 4 This is a comparison of the HER polarization curves of Example 1, Comparative Examples 1-2, and commercial Pt / C in 0.5 M H2SO4 electrolyte. From... Figure 4 It can be seen from the data that P-MoS2 / MoO2 at 10, 50, and 100 mA cm⁻¹ -2 At the specified current densities, the hydrogen evolution overpotentials were 67, 164, and 233 mV, respectively, which were superior to those of other comparative examples. This indicates that, through the synergistic effect of P doping, vacancies, and heterostructure, P-MoS2 / MoO2 exhibits excellent hydrogen evolution performance in acidic electrolytes.
[0045] Figure 5 This is a comparison of the Tafel slope of hydrogen evolution in Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte. From... Figure 5 As can be seen from this, the Tafel slope of the hydrogen evolution reaction of P-MoS2 / MoO2 is 69 mV dec. -1 The results are superior to other comparative examples. This indicates that, under the synergistic effect of P doping, vacancies, and heterostructure, P-MoS2 / MoO2 exhibits faster reaction kinetics during the hydrogen evolution reaction.
[0046] Figure 6 This is a comparison of the OER polarization curves of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte. From... Figure 6 As can be seen from this, P-MoS2 / MoO2 at 10 mA cm⁻¹ -2At a current density of 10⁴ mV, the oxygen evolution overpotential is 10⁴ mV, which is superior to other comparative examples. This indicates that, under the synergistic effect of P doping, vacancies, and heterostructure, P-MoS₂ / MoO₂ exhibits excellent oxygen evolution performance in acidic electrolytes.
[0047] Figure 7 This is a comparison of the oxygen evolution Tafel slopes of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte. From... Figure 7 As can be seen from this, the Tafel slope of the oxygen evolution reaction of P-MoS2 / MoO2 is 80 mV dec. -1 The results are superior to other comparative examples. This indicates that, under the synergistic effect of P doping, vacancies, and heterostructure, P-MoS2 / MoO2 exhibits faster reaction kinetics in the oxygen evolution reaction.
[0048] Figure 8 The electrochemical impedance spectroscopy (EIS) spectra of Examples 1 and Comparative Examples 1-2 in 0.5 M H₂SO₄ electrolyte are shown. Figure 8 As can be seen from the data, the charge transfer impedance of P-MoS2 / MoO2 is significantly lower than that of P-MoS2 and MoS2, indicating that the synergistic effect of P doping, vacancies and heterostructure can promote charge transfer at the catalyst-electrolyte interface.
[0049] Figure 9 This is a comparison of the total water electrolysis polarization curves of Example 1 and Comparative Examples 1-2 in 0.5 M H2SO4 electrolyte. From... Figure 9 As can be seen from this, when the current density is 10 mA cm⁻¹ -2 At that time, the cell voltage of P-MoS2 / MoO2||P-MoS2 / MoO2 was 1.44 V, which was lower than that of P-MoS2||P-MoS2 (1.61 V) and MoS2||MoS2 (1.76 V), indicating that the P-doped double-vacancy heterostructure catalyst P-MoS2 / MoO2 performed well in reducing the total water splitting voltage and improving electrochemical performance.
[0050] Figure 10 The figure shows the chronoamperometry response in 0.5 M H₂SO₄ electrolyte for Example 1. During continuous electrolysis testing, P-MoS₂ / MoO₂ exhibited good current stability. After 20 hours of testing, the current retention rate was 92%.
[0051] Figure 11 , 12 The images shown are scanning electron microscope (SEM) images and XRD patterns after the stability test in Example 1. The results demonstrate that the morphology, structure, and composition of P-MoS2 / MoO2 remained unchanged, indicating that P-MoS2 / MoO2 exhibits good structural stability during long-term electrocatalytic operation.
[0052] Figure 13 This is a comparison of the battery voltages of Example 1 and existing products in a 0.5 M H2SO4 electrolyte for complete water splitting. The battery voltage of P-MoS2 / MoO2 is significantly lower than that of most reported similar bifunctional electrocatalysts, demonstrating that P-MoS2 / MoO2 has great application potential in practical electrocatalytic water splitting.
[0053] Figure 14 The image shows the Faraday efficiency diagram for Example 1. The results demonstrate that the number of moles of released gas matches the theoretical calculation, and the molar ratio of generated H2 to O2 is close to 2:1, indicating that the Faraday efficiency of P-MoS2 / MoO2 is close to 100%.
[0054] This invention relates to a phosphorus-doped dual-vacancy heterostructure catalyst, which in particular uses polyacids as precursors and achieves acidic electrocatalytic total water splitting through dual-vacancy and heterostructure regulation.
[0055] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be included within the scope of protection of the present invention. Furthermore, all content not described in detail in this specification is prior art known to those skilled in the art.
Claims
1. A phosphorus-doped dual-vacancy heterostructure material, characterized in that, include: A conductive substrate and a composite nanostructure grown on the conductive substrate; the composite nanostructure includes a phosphorus-doped molybdenum disulfide phase containing sulfur vacancies and a molybdenum dioxide phase containing oxygen vacancies, wherein the molybdenum disulfide phase and the molybdenum dioxide phase are composited in situ to form a heterostructure.
2. The material according to claim 1, characterized in that, The conductive substrate is one of carbon cloth, carbon paper, nickel foam, or metal foil.
3. The material according to claim 1, characterized in that, The composite nanostructure is an array of nanosheets grown in a vertically intersecting manner.
4. The material according to claim 1, characterized in that, The X-ray diffraction pattern of the material contains diffraction peaks belonging to both molybdenum disulfide and molybdenum dioxide.
5. A method for preparing a phosphorus-doped double-vacancy heterostructure material as described in any one of claims 1-4, characterized in that, Includes the following steps: S1. Provide a precursor solution containing molybdenum source, phosphorus source and sulfur source, and grow phosphorus-doped P-MoS2 rich in sulfur vacancies on a pretreated conductive substrate by hydrothermal method. S2. Under an inert or reducing atmosphere, the conductive substrate loaded with P-MoS2 obtained in step S1 is heat-treated to convert some of the P-MoS2 into MoO2 rich in oxygen vacancies in situ, thereby forming a P-MoS2 / MoO2 heterostructure.
6. The method according to claim 5, characterized in that, In step S1, the molybdenum source and phosphorus source are phosphomolybdic heteropoly acids or their salts.
7. The method according to claim 6, characterized in that, The phosphomolybdic heteropolyacid is (NH4)6[P2Mo 18 O 62 ]·14H2O.
8. The method according to claim 5, characterized in that, In step S1, the hydrothermal reaction temperature is 180-220℃ and the reaction time is 18-30 hours; in step S2, the heat treatment temperature is 350-450℃ and the time is 2-4 hours.
9. The application of a phosphorus-doped double-vacancy heterostructure material as described in any one of claims 1-4 in an electrolytic water hydrogen production device.
10. The application according to claim 9, characterized in that, The material is used as a catalyst for the cathode hydrogen evolution reaction or the anode oxygen evolution reaction in water electrolysis.