High-efficiency hydrogen evolution method of monatomic catalyst

Abstract

The invention provides an efficient hydrogen evolution method of a monatomic catalyst, and relates to the technical field of monatomic catalytic materials. The monatomic catalyst is used for efficiently separating out hydrogen, the monatomic catalyst is ZnIn2S4, the Gibbs free energy (delta GH *) adsorbed by the hydrogen is commonly used for representing the catalytic activity of a hydrogen separation reaction (HER), the ZnIn2S4 has a typical layered structure and is hexagonal in atomic arrangement, the lattice parameter of the ZnIn2S4 is # imgabs0 # gamma = 120 degrees, the ZnIn2S4 can be regarded as being composed of a ZnS layer and an In2S3 layer, and the ZnS layer and the In2S3 layer are arranged in a hexagonal manner. The layers are connected through a Zn-S bond, the bond length of the Zn-S bond is # imgabs 1 #, the calculated lattice parameter of ZnIn2S4-Sv is # imgabs 2 # smaller than that of ZnIn2S4, and the catalytic activity of the hydrogen evolution reaction (HER) is Gibbs free energy (delta GH *) of hydrogen adsorption. Through the experiment, after the defects are introduced, the S-vacancy and the In-vacancy can enhance the charge transfer between the ZnIn2S4 layers.

Description

Technical Field The present invention relates to the technical field of single-atom catalytic materials, and in particular to a method for efficiently producing hydrogen by a single-atom catalyst. Background Art The single-atom metal catalyst formed by dispersing metal in the form of single atoms on the surface of a solid support not only has the characteristics of heterogeneous catalysis but also has the characteristics of homogeneous catalysis. In recent years, single-atom catalysts have developed rapidly in gas-phase reactions, organic reactions, electrocatalytic reactions and other reactions and have found wide applications. Referring to the following literature, ZnIn2S4 is widely used as a catalyst in clean energy conversion technology. However, due to the lack of doping, vacancy engineering, strain application and other methods, the performance of the catalyst has not been improved, and due to the relatively poor stability of single ZnIn2S4, the effect is not obvious when preparing a single-atom catalyst. Compared with the following literature, using ΔG H* , and introducing a single metal atom on the surface of ZnIn2S4 can improve the stability of the catalyst. Background Art Literature:

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[0008] SehZW, Fredrickson KD, Anasori B, et al. Two-dimensional molybdenum carbide (MXene) as an efficient electrocatalyst for hydrogen evolution[J]. ACS Energy Letters, 2016, 1(3):589-594. Zheng Y, Jiao Y, Jaroniec M, et al. Advancing the electrochemistry of the hydrogen-evolution reaction through combining experiment and theory[J]. Angewandte Chemie International Edition, 2015, 54(1):52-65. Summary of the Invention (1) Technical Problem to be Solved In view of the deficiencies of the prior art, the present invention provides a method for efficient hydrogen evolution of a single-atom catalyst, which solves the problem of the influence of introduced defects on the catalytic performance. (2) Technical Solution To achieve the above object, the present invention is realized through the following technical solutions: A method for efficient hydrogen evolution of a single-atom catalyst, the single-atom catalyst is ZnIn2S4, and the Gibbs free energy of hydrogen adsorption (ΔG H* ) is commonly used to characterize the catalytic activity of the hydrogen evolution reaction (HER); The operation steps for preparing ZnIn2S4 are as follows: Step 1: Prepare 30 g of zinc source, 60 g of indium source, 90 g of sulfur source, 500 g of deionized water, 100 ML of hydrogen, and 40 g of Fe; Step 2: Stir and mix the zinc source: indium source: sulfur source: deionized water in a ratio of 1:2:4:8; Step 3: Transfer the mixed solution in S2 to a sealed high-temperature and high-pressure reaction kettle, heat it at 50 °C for 8 hours to obtain ZnIn2S4; Step 4: After heating, allow the reaction kettle to cool naturally to room temperature (23 °C), and use a centrifuge to separate the generated ZnIn2S4 precipitate from the solution; Step 5: Wash the separated ZnIn2S4 precipitate with deionized water to remove impurities attached to the surface. After washing, dry the precipitate in a cabinet at 140 °C to obtain clean ZnIn2S4 powder; Step 6: Take 30 g of Fe and mix it with the clean ZnIn2S4 powder obtained in S5. Use Fe as a catalyst to react with ZnIn2S4 to promote the interaction between hydrogen and ZnIn2S4. Preferably, it includes the following steps: Step 1: The catalytic performance of ZnIn2S4 can be improved by means such as doping, vacancy engineering, and strain application; Step 2: Connect through Zn-S bonds, and the bond length of the Zn-S bond is Synthesized ZnIn2S4 with sulfur vacancies (ZnIn2S4-S v ); Step 3: Construct the structure of ZnIn2S4-S v and, for comparative analysis, also construct a model of ZnIn2S4 with indium vacancies (ZnIn2S4-In v ); Step 4: Study the HER catalytic performance of the original ZnIn2S4. After complete relaxation, the results show that hydrogen atoms cannot be stably adsorbed on the bridge site and vacancy, but are adsorbed on the top sulfur site (top-S); To further improve the catalytic performance of ZnIn2S4, single metal atoms are introduced on its surface, denoted as TM / ZnIn2S4, and the operation steps are as follows: Step 1: Add long-term stable single-atom catalysts (SACs); Step 2: Introduce defects, analyze the overall quantity of E ad and conduct Bader charge analysis; Step 3: Take the Fe system as an example and calculate the charge density difference (CDD); Step 4: Study the relationship between the charge distribution and the metal atom E ad and investigate the proportional relationship between the charge number (q) of the metal atom and E ad ; Step 5: Calculate the density of states of all systems to understand the changes in E ad in different systems; Step 6: By establishing the proportional relationship between the d-band center (ε d ) of the transition metal (TM) and E ad , further understand that the E ad of Co and Fe group elements is stronger than that of Cu group elements and the relationship between stability and electronic structure; By calculating the ΔG v of TM / ZnIn2S4, TM / ZnIn2S4-In v and TM / ZnIn2S4-S H* , the operation steps are as follows; Step 1. Observe the differences in hydrogen adsorption of TM / ZnIn2S4 on different transition metal atoms. Step 2. Compare Rh, Ir, and Ru with other metals; Step 3. Use ΔG H* to calculate the theoretical i0; Understand the correlation between the performance of the catalyst and its electronic structure: Step 1. Add copper (Cu), nickel (Ni), and iron (Fe) elements to hydrogen atoms in the d-orbital mesopores respectively; Step 2. Calculate the charge density difference of Ag / ZnIn2S4 and Os / ZnIn2S4; Step 3. Observe whether there is a charge transfer between Ag atoms and Os atoms and the substrate following the "donation - acceptance" mechanism. Preferably, the ZnIn2S4 has a typical layered structure with a hexagonal atomic arrangement, and the lattice parameters of the ZnIn2S4 are γ = 120°, and the ZnIn2S4 can be regarded as composed of ZnS layers and In2S3 layers, and these layers are connected by Zn - S bonds, and the bond length of the Zn - S bond is The calculated lattice parameters of ZnIn2S4 - S v are smaller than those of ZnIn2S4, and the catalytic activity of the hydrogen evolution reaction (HER) is expressed by the Gibbs free energy of hydrogen adsorption (ΔG H* ), and the positive ΔG H* indicates that the adsorption of hydrogen on the catalyst surface is unfavorable, while the negative ΔG H* indicates that the desorption of hydrogen is unfavorable. Preferably, there are four potential hydrogen atom adsorption sites on the ZnIn2S4, namely the top - sulfur site (top - S), the top - zinc site (top - Zn), the bridge site, and the hollow site. Preferably, the effects of the ΔG v values of the vacancy ZnIn2S4 - In v and ZnIn2S4 - S H* on the top - sulfur site on the catalytic performance, the hydrogen adsorption on the ZnIn2S4 becomes stronger, and the ΔG v values of ZnIn2S4 - In v and ZnIn2S4 - S H* are - 1.3 and - 1.07 eV respectively. Preferably, the E ad of all systems are negative values, indicating their thermodynamic stability. After introducing defects, the amount of charge transfer between metal atoms and the substrate increases, and q and Ead There is a positive correlation, and the E of the Co and Fe group elements ad is stronger than that of the Cu group elements. Preferably, the ΔG values of Rh / ZnIn2S4 and Os / ZnIn2S4 are the most negative, being -0.23 and -0.17 eV respectively. The ΔG values of Rh / ZnIn2S4-In H* 、Ir / ZnIn2S4-In v and Ir / ZnIn2S4-S v are 0.06, 0 and 0 eV respectively. v The ΔG H* value (III) Beneficial effects The present invention provides a method for highly efficient hydrogen evolution of a single-atom catalyst. It has the following beneficial effects: 1. By studying the regulation mechanism of catalytic performance introduced by surface defects, sulfur vacancies (S-vacancy) and indium vacancies (In-vacancy) can enhance the charge transfer between ZnIn2S4 layers. The reconstruction of the surface charge of ZnIn2S4 regulates its catalytic performance. The calculated ΔG of Pt / ZnIn2S4 is 0.02 eV, confirming its excellent catalytic performance for the hydrogen evolution reaction (HER). Ir / ZnIn2S4-S H* and Ir / ZnIn2S4-In v are potential highly efficient single-atom catalysts (SACs) for HER. v 2. The positive ΔG value in the present invention indicates that the adsorption of hydrogen on the catalyst surface is unfavorable, while the negative ΔG value H* indicates that the desorption of hydrogen is unfavorable. When ΔG H* should be close to 0, it is an ideal HER catalyst. The adsorption of hydrogen is the most stable at the apical sulfur site, and ΔG H* is -0.69 eV, lower than 1.69 eV at the apical zinc site (top-Zn). The relatively negative and relatively positive ΔG H* values indicate that neither the apical sulfur site nor the apical zinc site is suitable as an ideal HER active site. H* 3. Introducing a single metal atom on the surface of ZnIn2S4 can improve the catalytic performance. The E values of all systems are negative, indicating their thermodynamic stability. In addition, the electronic structure of the metal atom is the main determinant of the adsorption strength. As the number of pore sites in the metal atom increases, the amount of charge transfer between the metal atom and the substrate increases, resulting in an increase in E. ad ad Brief description of the drawings Figure 1(a) Original ZnIn2S4; (b) ZnIn2S4-In v ; (c) ZnIn2S4-S v , the spheres represent the Zn, S and In elements respectively, and the positions marked by circles are schematic diagrams of the positions of vacancies; Figure 2 : Geometric structure diagram of ZnIn2S4, showing the situation of hydrogen adsorption at different positions: (a) top-S site (b) top-Zn site (c) bridge site (d) vacancy (e) hydrogen evolution reaction (HER) reaction coordinate on pristine ZnIn2S4 (f) reaction coordinate on pristine ZnIn2S4, ZnIn2S4-In v and ZnIn2S4-S v (Top-S position) hydrogen evolution reaction coordinate; Figure 3 :(a) Adsorption energy (E) of various single atom catalysts (SACs) ad ); (b) Bader charge of various SACs; (c) Charge density difference of Fe / ZnIn2S4; (d) Fe / ZnIn2S4-In v Charge density difference; (e) Fe / ZnIn2S4-S v The charge density difference of S is Represents electron accumulation, Zn isosurface Indicates electron depletion. (f) The d-band center of Fe / ZnIn2S4 (ε d ) and the proportional relationship between adsorption energy; (g) Fe / ZnIn2S4-In v The d-band center (ε d ) and the proportional relationship between the adsorption energy; (h) Fe / ZnIn2S4-S v The d-band center (ε d ) and the calculated proportional relationship between adsorption energy; Figure 4 : (a) ΔG of all considered systems H* Value; (b) Theoretical exchange current density of TM / ZnIn2S4; (c) TM / ZnIn2S4-In v Theoretical exchange current density; (d) TM / ZnIn2S4-S v The theoretical exchange current density of Figure 5 :(a) d-band center of TM / ZnIn2S4 (ε d ) and ΔG H* The ratio between them; (b) TM / ZnIn2S4-In v The d-band center (ε d ) and ΔGH* The proportional relationship between; (c) TM / ZnIn2S4-S v The d-band center of (ε d ) and ΔG H* The proportional relationship between. (d) Charge density difference of ZnIn2S4; (e) ZnIn2S4-In v Charge density difference of; (f) ZnIn2S4-S v Charge density difference of, S isosurface Indicates electron accumulation, Zn isosurface Indicates electron depletion; Figure 6 : Geometric structure of TM / ZnIn2S4, spheres represent Zn, S, and TM (transition metal) atoms respectively; Figure 7 : Proportional relationship between S2q and adsorption energy (E ad ); Figure 8 : Density of states of TM / ZnIn2S4; Figure 9 : TM / ZnIn2S4-In v Density of states of; Figure 10 : TM / ZnIn2S4-S v Density of states of; Figure 11 : (a) Charge density difference of Ag / ZnIn2S4 (b) Charge density difference of Os / ZnIn2S4, S isosurface Indicates electron accumulation, Zn isosurface Indicates electron vacancy. Specific implementation mode Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Embodiment 1: As Figures 1-11 shown, the embodiment of the present invention provides a method for highly efficient hydrogen evolution of a single-atom catalyst. The single-atom catalyst is ZnIn2S4, and the Gibbs free energy of hydrogen adsorption (ΔG H* ) is often used to characterize the catalytic activity of the hydrogen evolution reaction (HER); The operation steps for preparing ZnIn2S4 are as follows: Step 1: Prepare 30 g of zinc source, 60 g of indium source, 90 g of sulfur source, 500 g of deionized water, 100 mL of hydrogen gas, and 40 g of Fe; Step 2: Stir and mix the zinc source: indium source: sulfur source: deionized water in a ratio of 1:2:4:8; Step 3: Transfer the mixed solution in S2 to a sealed high-temperature and high-pressure reactor, heat it at 50 °C for 8 hours to obtain ZnIn2S4; Step 4: After heating is completed, allow the reactor to cool naturally to room temperature (23 °C), and use a centrifuge to separate the generated ZnIn2S4 precipitate from the solution; Step 5: Wash the separated ZnIn2S4 precipitate with deionized water to remove impurities attached to the surface. After washing, dry the precipitate in a cabinet at 140 °C to obtain clean ZnIn2S4 powder; Step 6: Take 30 g of Fe and mix it with the clean ZnIn2S4 powder obtained in S5. Use Fe as a catalyst to react with ZnIn2S4 to promote the interaction between hydrogen gas and ZnIn2S4; It includes the following steps: Step 1: The catalytic performance of ZnIn2S4 can be improved by means such as doping, vacancy engineering, and strain application; Step 2: Connected by Zn-S bonds, and the bond length of the Zn-S bond is Synthesized ZnIn2S4 with sulfur vacancies (ZnIn2S4-S v ); Step 3: Construct the structure of ZnIn2S4-S v and, for comparative analysis, also construct a model of ZnIn2S4 with indium vacancies (ZnIn2S4-In v ); Step 4: Study the HER catalytic performance of the original ZnIn2S4. After complete relaxation, the results show that hydrogen atoms cannot be stably adsorbed on the bridge site and vacancy, but are adsorbed on the top sulfur site (top-S); To further improve the catalytic performance of ZnIn2S4, a single metal atom is introduced on its surface, denoted as TM / ZnIn2S4, and its operation steps are as follows: Step 1: Add long-term stable single-atom catalysts (SACs); Step 2: Introduce defects, and analyze the overall quantity of E ad and perform Bader charge analysis; Step 3: Taking the Fe system as an example, calculate the charge density difference (CDD); Step 4: Study the charge distribution and the metal atom E adThe relationship between the charge number (q) of metal atoms and E ad The proportional relationship between them; Step 5: Calculate the density of states of all systems to understand the change of E in different systems ad ; Step 6: By establishing the proportional relationship between the d-band center (ε d ) of transition metal (TM) and E ad , further understand that the E of Co and Fe group elements is stronger than that of Cu group elements and the relationship between stability and electronic structure; ad ; By calculating the ΔG of TM / ZnIn2S4, TM / ZnIn2S4-In v and TM / ZnIn2S4-S v , the operation steps are as follows; H* ; Step 1: Observe the differences in hydrogen adsorption of TM / ZnIn2S4 on different transition metal atoms. Step 2: Compare Rh, Ir and Ru with other metals; Step 3: Calculate the theoretical i0 using ΔG H* ; Understand the correlation between the performance of the catalyst and its electronic structure: Step 1: Add copper (Cu), nickel (Ni) and iron (Fe) elements to the hydrogen atoms in the d-orbital pores respectively. Compared with the Cu group elements, although the d-orbitals of the Ni group elements have no obvious contribution above the Fermi level, they are closer to the Fermi level as a whole; Step 2: Calculate the charge density difference of Ag / ZnIn2S4 and Os / ZnIn2S4; Step 3: Observe whether there is a charge transfer between Ag atoms and Os atoms and the substrate following the "donation-acceptance" mechanism. ZnIn3S4 has a typical layered structure with a hexagonal atomic arrangement. The lattice parameter of ZnIn2S4 is γ = 120°. ZnIn2S4 can be regarded as composed of ZnS layers and In2S3 layers, and these layers are connected by Zn-S bonds. The bond length of the Zn-S bond is Calculated that the lattice parameter of ZnIn2S4-S v is smaller than that of ZnIn2S4. The catalytic activity of the hydrogen evolution reaction (HER) is expressed by the Gibbs free energy of hydrogen adsorption (ΔG H* ). A positive ΔG H* indicates that the adsorption of hydrogen on the catalyst surface is unfavorable, while a negative ΔG H *This indicates that the desorption of hydrogen is unfavorable. There are four potential hydrogen atom adsorption sites on ZnIn2S4, namely, the top sulfur site (top-S), the top zinc site (top-Zn), the bridge site (bridge) and the hollow site (hollow). v and ZnIn2S4-S v ΔG at the apical sulfur position H* The effect of the value on the catalytic performance, the hydrogen adsorption on ZnIn2S4 becomes stronger, and the ZnIn2S4-In v and ZnIn2S4-S v ΔG H* are -1.3 and -1.07 eV respectively. The E ad are all negative, indicating that they are thermodynamically stable. After the introduction of defects, the charge transfer between metal atoms and the substrate increases, and q is related to E ad There is a positive correlation between the number of electrons in the outer layer of the metal and the substrate. When the number of electrons in the outer layer of the metal increases, the interaction between the metal atoms and the substrate weakens. The electronic structure of the metal atoms is the key factor determining the E ad The key factor is that the d orbitals of copper group elements are fully occupied and lack sufficient empty orbitals to accept electrons. For copper group elements, their 3d orbitals are mainly at the top, and the E ad Stronger than Cu group elements, ΔG of Rh / ZnIn2S4 and Os / ZnIn2S4 H * The values ​​are the most negative, -0.23 and -0.17 eV respectively. The Rh, Ir and Ru systems show better catalytic activity. Rh / ZnIn2S4-Inv, Ir / ZnIn2S4-Inv v and Ir / ZnIn2S4-S v ΔG H* The values ​​are 0.06, 0 and 0 eV respectively. Excessive hydrogen adsorption is not conducive to the HER process. It is worth noting that the ΔG of Pt / ZnIn2S4 H* The value is only 0.02 eV, which indicates that its HER activity is better than that of Pt(111). With the introduction of defects, the adsorption of hydrogen on the catalyst surface is enhanced, following the HER performance trend observed in unsupported metal systems, indicating that the loading of surface metals has no obvious effect on the regulation of catalytic performance through defects. Embodiment 2: Figure 1 As shown in a, the lattice parameters of the original ZnIn2S4 are calculated to be γ=120°, ZnIn2S4 can be regarded as composed of ZnS layer and In2S3 layer, which are connected by Zn-S bond, and the bond length of Zn-S bond is Vacancies can change the interactions between layers, e.g.Figure 2 As shown in a-d. After complete relaxation, the results show that hydrogen atoms cannot be stably adsorbed on the bridge site and the vacancy, but are adsorbed on the top sulfur site (top-S). Figure 2 As shown in e, hydrogen adsorption is the most stable on the top sulfur site, with ΔG H* being -0.69 eV, lower than 1.69 eV of the top zinc site (top-Zn). More negative and more positive ΔG H* values indicate that neither the top sulfur site nor the top zinc site is suitable as an ideal HER active site. As Figure 6 shown, a single metal atom was introduced onto the ZnIn2S4 surface, denoted as TM / ZnIn2S4. The adsorption energy (E ad ) of different transition metal atoms on these structures was calculated. As Figure 3 shown in a, in order to better understand the charge transfer between the metal atom and the substrate, Bader charge analysis was carried out ( Figure 3 b). After introducing defects, the amount of charge transfer between the metal atom and the substrate increases. Taking the Fe system as an example, the charge density difference (CDD) was calculated ( Figure 3 c-e). In the ZnIn2S4-In v / ZnIn2S4-S v system, the charge transfer between the metal atom and the substrate is more obvious than that in ZnIn2S4. Using ΔG H* the theoretical i0 was calculated (as Figure 4 shown in b-d), which is an important method for screening highly efficient HER catalysts. There is usually a volcano curve between i0 and ΔG H* . Catalysts close to the top of the volcano curve show superior catalytic performance. Obviously, Ru and Os show strong hydrogen adsorption and they are located on the left side of the volcano curve. In contrast, the hydrogen adsorption of Cu and Ag is very weak and they are located on the right side of the volcano curve. However, hydrogen adsorption should neither be too strong nor too weak to be an ideal catalyst. In these systems, Pt / ZnIn2S4, Ir / ZnIn2S4-In v and Ir / ZnIn2S4-S v show excellent performance in HER catalytic activity. To understand the change in charge transfer between different metal atoms and the substrate, taking Ag / ZnIn2S4 and Os / ZnIn2S4 as examples, their charge density differences (CDD) were calculated. Elements of the iron (Fe) group have the ability to both acquire and lose electrons due to the relatively large number of holes in their d orbitals, resulting in a strong interaction with hydrogen atoms. As Figure 11As shown, there is mainly an electron depletion region around the Ag atom, which means that electrons are mainly transferred from Ag to the substrate. On the contrary, around the Os atom, there are not only electron accumulation regions but also electron depletion regions, indicating that the charge transfer between the Os atom and the substrate follows the "donation - acceptance" mechanism. This obvious difference in the charge transfer mechanism ultimately leads to a significant difference in catalytic performance. In addition, when an Fe atom is loaded onto the substrate, it transfers nearly one electron (0.82e in Fe / ZnIn2S4 - , Fe / ZnIn2S4-In v is 0.98e - , Fe / ZnIn2S4-S v is 0.89e - ) to the substrate. This charge transfer makes the d orbitals of Fe in a half - filled state, thus reducing its ability to transfer charge to hydrogen atoms, resulting in a larger ΔG H* value of Fe than that of Ru and Os. To further explore the regulation mechanism of defects on catalytic performance, the charge density differences (CDD) of ZnIn2S4, ZnIn2S4-In v and ZnIn2S4-S v were calculated and compared, as shown in Figure 5 . For the original ZnIn2S4, a slight charge transfer (0.23e -) occurs from the ZnS layer to the In2S3 layer ( Figure 5 a). After introducing defects, the charge is redistributed. ZnIn2S4-S v shows obvious electron accumulation regions around S v , mainly from the transfer of more electrons (0.67e -) from the ZnS layer to the In2S3 layer. ZnIn2S4-S v shows a more significant electron depletion region on the ZnS surface, indicating the existence of favorable active sites that contribute to stabilizing hydrogen atoms. For ZnIn2S4-In v , the electron depletion region on the ZnS surface is the most significant, which makes ZnIn2S4-In v have the most negative ΔG H* value among these three systems. Generally speaking, the introduction of defects induces charge transfer between layers, leading to the reconstruction of surface charges and further regulating catalytic performance. Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for efficient hydrogen evolution of a single-atom catalyst, characterized in that, The single-atom catalyst is ZnIn2S4, and the Gibbs free energy of hydrogen adsorption (ΔG H* ) is commonly used to characterize the catalytic activity of the hydrogen evolution reaction (HER); The operating steps for preparing ZnIn2S4 are as follows: Step 1: Prepare 60 g of zinc source, 90 g of indium source, 200 g of sulfur source, 600 g of deionized water, 300 ml of hydrogen, and 40 g of Fe; Step 2: Stir and mix the zinc source: indium source: sulfur source: deionized water in a ratio of 2:4:6:10; Step 3: Transfer the mixed solution in S2 to a sealed high-temperature and high-pressure reactor, heat it at 50 °C for 8 hours to obtain ZnIn2S4; Step 4: After heating is completed, allow the reactor to cool naturally to room temperature (23 °C), and use a centrifuge to separate the generated ZnIn2S4 precipitate from the solution; Step 5: Wash the separated ZnIn2S4 precipitate with deionized water to remove impurities attached to the surface. After washing, dry the precipitate in a cabinet at 140 °C to obtain clean ZnIn2S4 powder; Step 6: Take 30 g of Fe and mix it with the clean ZnIn2S4 powder obtained in S5. React Fe as a catalyst with ZnIn2S4 and interact with 270 ml of hydrogen and ZnIn2S4.

2. The method for highly efficient hydrogen evolution of a single-atom catalyst according to claim 1, wherein: It includes the following steps: Step 1: The catalytic performance of ZnIn2S4 can be improved by means such as doping, introducing vacancies, and applying strain; Step 2: Connect through Zn-S bonds, and the bond length of the Zn-S bond is ZnIn2S4 with sulfur vacancies (ZnIn2S4-S v ) was synthesized; Step 3: Construct the structure of ZnIn2S4-S v and, for comparative analysis, also construct a model of ZnIn2S4 with indium vacancies (ZnIn2S4-In v ); Step 4: Study the HER catalytic performance of the original ZnIn2S4. After complete relaxation, the results show that hydrogen atoms cannot be stably adsorbed on the bridge site and vacancy, but are adsorbed on the top sulfur site (top-S); In order to further improve the catalytic performance of ZnIn2S4, a single metal atom is introduced on its surface, denoted as TM / ZnIn2S4. The operating steps are as follows: Step 1: Add long-term stable single-atom catalysts (SACs); Step 2, introduce defects, and evaluate its stability and catalytic performance and perform Bader charge analysis by calculating and analyzing E ad ; Step 3: Take the Fe system as an example and calculate the charge density difference (CDD); Step 4: Study the relationship between the charge distribution and metal atom E ad and investigate the proportional relationship between the charge number (q) of the metal atom and E ad ; Step 5: Calculate the density of states of all systems to understand the changes in Ead in different systems; Step 6. By establishing the proportional relationship between the d-band center (ε d ) of transition metal (TM) and E ad , further understand that the E ad of Co and Fe group elements is stronger than that of Cu group elements and the relationship between stability and electronic structure; By calculating the ΔG of TM / ZnIn2S4, TM / ZnIn2S4-In v and TM / ZnIn2S4-S v , the operation steps are as follows; H* ​ Step 1: Observe the differences in hydrogen adsorption of TM / ZnIn2S4 on different transition metal atoms. Step 2: Compare Rh, Ir, and Ru with other metals; Step 3, using ΔG H* calculated the theoretical exchange current i0; Understand the correlation between the performance of the catalyst and its electronic structure: Step 1: Add copper (Cu), nickel (Ni), and iron (Fe) elements to hydrogen atoms in the d-orbital mesopores respectively; Step 2: Calculate the charge density difference of Ag / ZnIn2S4 and Os / ZnIn2S4; Step 3: Observe whether there is a charge transfer between Ag atoms and Os atoms and the substrate following the "donation-acceptance" mechanism.

3. The highly efficient hydrogen evolution reaction of a single-atom catalyst according to claim 2, characterized in that: The ZnIn2S4 has a typical layered structure with a hexagonal atomic arrangement. The lattice parameters of the ZnIn2S4 are γ = 120°. The ZnIn2S4 can be regarded as being composed of ZnS layers and In2S3 layers, and these layers are connected by Zn-S bonds. The bond length of the Zn-S bond is The calculated lattice parameters of ZnIn2S4-S v are smaller than those of ZnIn2S4. The catalytic activity of the hydrogen evolution reaction (HER) is characterized by the Gibbs free energy of hydrogen adsorption (ΔG H* ). A positive ΔG H* indicates unfavorable hydrogen adsorption on the catalyst surface, while a negative ΔG H* indicates unfavorable hydrogen desorption.

4. A method for efficient hydrogen evolution of a single-atom catalyst according to claim 2, characterized in that: The four potential hydrogen atom adsorption sites on the ZnIn2S4 are the top sulfur site (top-S), the top zinc site (top-Zn), the bridge site, and the hollow site respectively.

5. A method for highly efficient hydrogen evolution of a single-atom catalyst according to claim 4, characterized in that: The vacant site ZnIn2S4-In v and ZnIn2S4-S v The influence of the ΔG value on the catalytic performance at the top sulfur site. The hydrogen adsorption on ZnIn2S4 becomes stronger. The ZnIn2S4-In H* and ZnIn2S4-S v The ΔG v values are -1.3 and -1.07 eV respectively. H* ​ 6. The method for highly efficient hydrogen evolution of a single-atom catalyst according to claim 2, wherein: The E of all the systems ad are all negative values, indicating their thermodynamic stability. After introducing defects, the charge transfer amount between metal atoms and the substrate increases. There is a positive correlation between q and E ad . The E of Co and Fe group elements ad is stronger than that of Cu group elements.

7. A method for efficient hydrogen evolution of a single-atom catalyst according to claim 2, characterized in that: The ΔG of the Rh / ZnIn2S4 and Os / ZnIn2S4 H* values are the most negative, being -0.23 and -0.17 eV respectively. The ΔG of the Rh / ZnIn2S4-Inv, Ir / ZnIn2S4-In v and Ir / ZnIn2S4-S v are 0.06, 0, and 0 eV respectively. H* ​

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