Method and system for screening catalyst for preparing methanol by reducing carbon dioxide

Abstract

The invention provides a method and a system for screening a catalyst for preparing methanol by reducing carbon dioxide. The method comprises the following steps: calculating an optimized structure (CONNTCAR) and an energy value (OUTCAR) of a TM (at) Mo2C model; the formation energy Ef of the TM and Mo2C model is calculated; by calculating a POURBAIX graph, the coverage conditions of other species of molybdenum carbide under the working potential under the chemical reaction are determined; detailed electrocatalytic CO2RR and HER mechanisms of these catalysts are systematically discussed through density functional theory (DFT) calculation. The invention solves the technical problems of high experimental research cost and high difficulty in improvement of the performance of methanol preparation by carbon dioxide reduction due to undefined reaction mechanism of transition metal loaded molybdenum carbide for preparation of methanol by carbon dioxide reduction.

Description

Technical Field

[0001] The invention relates to the fields of chemistry and materials, and in particular to a catalyst screening method and system for preparing methanol by reducing carbon dioxide. Background Art

[0002] In recent years, the rapid increase in CO2 emissions has become a pressing environmental issue, exacerbating climate change and posing challenges to sustainable development. The electrochemical carbon dioxide reduction reaction (CO2RR) has emerged as a promising way to alleviate the energy crisis. This technology converts CO2 into a range of valuable chemicals, from C1 compounds such as carbon monoxide (CO), methane, and formic acid to C2 compounds such as ethylene, ethanol, and acetone. Each product has different uses, and each has different uses, thus not only reducing net CO2 emissions but also contributing to the circular carbon economy. However, a common challenge of CO2RR is the inevitable occurrence of hydrogen evolution reaction (HER). Therefore, it is crucial to find efficient and stable electrocatalysts that inhibit the hydrogen evolution reaction for CO2RR production.

[0003] Molybdenum carbide (Mo2C) is an important transition metal carbide with a series of special properties. First of all, it has high hardness and high melting point, which enables it to maintain stable performance under extreme conditions. In addition, molybdenum carbide exhibits good thermal stability and corrosion resistance, which is suitable for applications in harsh environments. In terms of surface properties, molybdenum carbide is similar to precious metals and has excellent adsorption properties, which makes it have important application potential in the field of catalysts. At the same time, compared with precious metals, the cost of molybdenum carbide is lower, which provides economic advantages for its promotion in industrial applications. In addition, molybdenum carbide also has high stability and can maintain its performance in a variety of environments. At the same time, its crystal phase and electronic properties are adjustable, which provides more possibilities for its applicability in different application fields. Therefore, molybdenum carbide is not only similar to precious metals in performance, but also has unique advantages, which makes it show good development prospects in materials science and industrial applications.

[0004] Single atom catalysts (SACs) show great promise in reducing catalyst costs and achieving high activity and selectivity due to their maximum atomic utilization and atomically tunable active structures. Transition metal carbides have become a promising support material for obtaining SACs due to their strong interactions with various transition metal atoms and relatively low cost. Molybdenum carbide is particularly noteworthy, whose tunable crystal phase and unique electronic properties make it a suitable platform for designing various SACs. For example, Ma and co-workers prepared single-atom dispersed Au, Pt, Ni and Ir atoms on α-MoC supports, which showed excellent activity in catalyzing water-gas shift reaction, methanol-water reforming and quinoline hydrogenation. These show the application prospects of materials supported by single atoms on molybdenum carbide.

[0005] The existing invention patent application document "A Ceria-supported Platinum Single Atom Catalyst and Its Structural Design Method" with publication number CN114725408A, the existing method includes: using Materials Studio or VESTA modeling software to construct CeO2 surface models with different orientations, including (111), (110) and (100) surfaces. Using Materials Studio or VESTA modeling software to construct CeO2 surface models with different orientations, including (111), (110) and (100) surfaces. The existing invention patent application document with publication number CN114914459A is "A method for screening the catalytic activity of manganese-based single-atom catalysts with anion surface modification". The existing method includes: constructing an anion functional group adsorption model, determining oxygen reduction active sites, constructing a key intermediate model of oxygen reduction reaction, calculating catalytic activity and constructing a catalytic activity volcano map. Through atomic scale model analysis, the influence of anion surface modification on the geometric configuration, ion valence, Bader charge, state density, spin magnetic moment, oxygen adsorption capacity, and oxygen reduction reaction intermediate adsorption capacity of the active center of the Mn-NC catalyst is studied, a method for screening anion functional group modification to improve the catalytic activity of the Mn-NC catalyst in the oxygen reduction reaction is established, and the optimal anion functional group modified Mn-NC catalyst is screened out. The existing public document "First Principles Study on Electrocatalytic Energy Conversion of Two-Dimensional Carbon-Containing Materials" takes two-dimensional carbon-containing material catalysts as the research object, and based on density functional theory calculations, the electrocatalytic energy conversion reactions of two-dimensional materials are studied in four dimensions: structural design, performance prediction, mechanism explanation, and application direction. The focus is on exploring the three electrochemical catalytic reactions that have attracted much attention from researchers: oxygen reduction (ORR), carbon dioxide reduction (CO,RR), and ammonia reduction reaction (NRR). They all involve the reduction reaction of common small molecule gases. The effects of modification methods such as doping, functional groups, and transition metal single atom loading on the electrochemical catalytic performance of materials were systematically studied. By calculating the formation energy and reaction path energy of the catalyst, the reaction activity, selectivity, and stability of the catalyst were comprehensively evaluated. However, the aforementioned prior art has not deeply studied the adsorption of other species on the catalyst surface at the working potential of carbon dioxide reduction, and it is difficult to use it to determine the full hydrogen adsorption on the molybdenum carbide surface. The performance of the catalyst disclosed in the aforementioned prior art for carbon dioxide reduction to produce methanol needs to be improved.

[0006] In summary, the existing technology has technical problems such as high experimental research costs and difficulty in improving the performance of preparing methanol by reducing carbon dioxide due to the unclear reaction mechanism of transition metal-loaded molybdenum carbide. Summary of the invention

[0007] The technical problem to be solved by the present invention is: to propose a molybdenum carbide-loaded Rh single-atom catalyst in order to improve the performance of carbon dioxide reduction to prepare methanol; due to the advantages of molybdenum carbide such as low cost, high stability, adjustable crystal phase, unique electronic properties and properties similar to those of precious metals, it is used as an excellent carrier for loading metals in the present invention to improve energy conversion efficiency.

[0008] The present invention adopts the following technical solutions to solve the above technical problems: including:

[0009] S1. Optimize the TM@Mo2C model to obtain an applicable TM@Mo2C model, and calculate the optimized structure CONTCAR and energy value OUTCAR of the applicable TM@Mo2C model;

[0010] S2. Calculate the formation energy E of the applicable TM@Mo2C model f , compare the formation energy E f The value of is used to obtain the comparison result, and the applicable catalyst model is selected from the applicable TM@Mo2C model according to the comparison result;

[0011] S3. Calculate the POURBAIX diagram according to the applicable catalyst model to determine the coverage of other species of molybdenum carbide at the preset working potential under the preset chemical reaction, and use the preset modeling tool to model the coverage of other species;

[0012] S4. Calculate the electrocatalytic CO2RR mechanism information and HER mechanism information of each pre-set catalyst through density functional theory DFT, and determine the catalyst suitable for CO2RR.

[0013] The technical problem to be solved by the present invention is that the existing technology is unclear about the reaction mechanism of carbon dioxide reduction to prepare methanol on transition metal-loaded molybdenum carbide. The present invention provides theoretical guidance for experimental research, saves the trial and error cost and time of the experiment, and accelerates the research process of the experiment.

[0014] In a more specific technical solution, S1 includes:

[0015] S11. Use the preset tools to import the Mo2C.cif file in the Materials project structure library, perform the primitive cell section operation through the Cleave Surfaces block, build the vacuum layer model, obtain and transform the minimum unit molybdenum carbide structure, and obtain the VASP-recognizable input file POSCAR;

[0016] S12, setting the input file, performing structural optimization operation and energy calculation on the minimum unit molybdenum carbide structure through VASP calculation software, and obtaining the optimized structure CONTCAR and energy value OUTCAR;

[0017] S13, using the preset modeling tool, expanding the minimum unit molybdenum carbide structure to obtain expanded molybdenum carbide, using VASP calculation software to perform structural optimization operation and energy calculation on the expanded molybdenum carbide to obtain the expanded cell optimized structure CONTCAR and the expanded cell energy value OUTCAR;

[0018] S14, constructing the transition metal-loaded molybdenum carbide structure TM@Mo2C for the expanded cell optimization structure CONTCAR, converting the transition metal-loaded molybdenum carbide structure TM@Mo2C into a VASP-recognizable input file POSCAR, and obtaining a suitable TM@Mo2C model;

[0019] S16. Perform structural optimization and energy calculation on the applicable TM@Mo2C model using VASP calculation software;

[0020] S17, repeat S11 to S16 to obtain the optimized structure CONTCAR and energy value OUTCAR.

[0021] In a more specific technical solution, in S12, the input files include: PBE functional description INCAR, VASP recognizable input files POSCAR, KPOINTS, POTCAR and scripts.

[0022] In a more specific technical solution, S12 also includes:

[0023] S121. Optimize the geometric structure of the molybdenum carbide material and obtain a CONTCAR file and an OUTCAR file;

[0024] S122, using VESTA to import the CONTCAR file and perform structural visualization processing to obtain structural information;

[0025] S123, extracting energy information from the OUTCAR file through VASP calculation;

[0026] S124. Use subwork as a script.

[0027] In a more specific technical solution, in S2, the following logic is used to process the formation energy E f :

[0028] E f =E(TM@Mo2C)-E(Mo2C)-u(TM)

[0029] Where E(TM@Mo2C) represents the energy of TM@Mo2C calculated by DFT; E(Mo2C) represents the energy of Mo2C calculated by DFT; u(TM) represents the chemical potential of the transition metal.

[0030] The present invention uses first-principles calculations to form a basis for judging the thermal stability of materials, thereby screening out transition metal-loaded molybdenum carbide materials with high stability.

[0031] In more specific technical solutions, S3 includes:

[0032] S31. Calculate the POURBAIX diagram using the following reaction relationship:

[0033] *+mH2O→HnOm*+(2m-n)(H + +e - )

[0034] ΔG(U,pH)=G(HnOm*)-G(*)-mG(H2O)+(2m-n)[1 / 2G(H2)-eU SHE -kBTln(10)pH]

[0035] Where ΔG(U, pH) represents the Gibbs free energy change; G(HnOm*) represents the free energy of the intermediate adsorption on TM@Mo2C; G(*) represents the energy of TM@Mo2C; G(H2O) represents the free energy of water; G(H2) represents the free energy of hydrogen; e represents the number of electrons; U SHE represents the standard hydrogen electrode; kB represents the Boltzmann constant; T represents temperature; pH represents the acidity and base value; m and n represent the number.

[0036] S32. Use the preset modeling tools to model the coverage of the remaining species.

[0037] In a more specific technical solution, in S32, the preset modeling tools include: Materials Studio modeling software.

[0038] In a more specific technical solution, in S4, according to the elementary operation, the optimization process is performed to obtain the carbon dioxide reduction to prepare methanol reaction and the hydrogen evolution reaction. The optimized structure CONTCAR and energy value OUTCAR of the reactants and each intermediate on the TM@Mo2C catalyst are obtained, and the catalyst suitable for CO2RR is obtained through energy screening operation.

[0039] The present invention calculates the POURBAIX diagram to obtain that the surface of transition metal-supported molybdenum carbide is fully covered with hydrogen under chemical reaction. Then, combined with the first principle, the performance of carbon dioxide reduction on the surface of transition metal-supported molybdenum carbide is calculated, and compared with the performance of carbon dioxide reduction on the copper surface, and the transition metal-supported molybdenum carbide material (Rh@Mo2C) with improved carbon dioxide reduction performance is screened out.

[0040] In a more specific technical solution, S4 includes:

[0041] S41. Using the following logic, the Gibbs free energy change ΔG of the Rh@Mo2C catalyst is obtained:

[0042] ΔG = ΔE + ΔZPE - TΔS;

[0043] Where ΔE represents the change in energy calculated by DFT; ΔZPE represents the frequency calculation; T represents the temperature; ΔS represents the change in entropy;

[0044] S42. Calculate the limiting potential U using the following logic: L :

[0045] U L =-ΔGmax / e.

[0047] The present invention systematically studies the performance of preparing methanol by reducing carbon dioxide on transition metal-supported molybdenum carbide through first-principles calculations, and uses the method to obtain a material (Rh@Mo2C) with improved performance of preparing methanol by reducing carbon dioxide.

[0048] In a more specific technical solution, a catalyst screening system for reducing carbon dioxide to produce methanol includes:

[0049] The structural data and energy value acquisition module is used to optimize the TM@Mo2C model, obtain the applicable TM@Mo2C model, and calculate the optimized structure CONTCAR and energy value OUTCAR applicable to the TM@Mo2C model;

[0050] Catalyst model screening module, used to calculate the formation energy E of the applicable TM@Mo2C model f , compare the formation energy E f The value of is used to obtain a comparison result. According to the comparison result, a suitable catalyst model is selected from the applicable TM@Mo2C model. The catalyst model selection module is connected with the structure data and energy value acquisition module.

[0051] A coverage modeling module is used to calculate the POURBAIX diagram according to the applicable catalyst model, determine the coverage of other species of molybdenum carbide at a preset working potential under a preset chemical reaction, and use a preset modeling tool to model the coverage of other species. The coverage modeling module is connected to the catalyst model screening module;

[0052] The catalyst determination module is used to calculate the electrocatalytic CO2RR mechanism information and HER mechanism information of each preset catalyst through density functional theory DFT, and determine the catalyst suitable for CO2RR. The catalyst determination module is connected to the coverage modeling module.

[0053] Compared with the prior art, the present invention has the following advantages:

[0054] The technical problem to be solved by the present invention is that the existing technology is unclear about the reaction mechanism of carbon dioxide reduction to prepare methanol on transition metal-loaded molybdenum carbide. The present invention provides theoretical guidance for experimental research, saves the trial and error cost and time of the experiment, and accelerates the research process of the experiment.

[0055] The present invention uses first-principles calculations to form a basis for judging the thermal stability of materials, thereby screening out transition metal-loaded molybdenum carbide materials with high stability.

[0056] The present invention calculates the POURBAIX diagram to obtain that the surface of transition metal-supported molybdenum carbide is fully covered with hydrogen under chemical reaction. Then, combined with the first principle, the performance of carbon dioxide reduction on the surface of transition metal-supported molybdenum carbide is calculated, and compared with the performance of carbon dioxide reduction on the copper surface, and the transition metal-supported molybdenum carbide material (Rh@Mo2C) with improved carbon dioxide reduction performance is screened out.

[0057] The present invention systematically studies the performance of preparing methanol by reducing carbon dioxide on transition metal-supported molybdenum carbide through first-principles calculations, and uses the method to obtain a material (Rh@Mo2C) with improved performance of preparing methanol by reducing carbon dioxide.

[0058] The present invention constructs a configuration of molybdenum carbide loaded with transition metals, determines the stability of the material, calculates POURBAIX to determine the coverage of surface species of molybdenum carbide at the working potential of carbon dioxide reduction, studies its reaction path, and designs a catalyst (Rh@Mo2C) with improved carbon dioxide reduction performance.

[0059] Compared with the existing scheme, the present invention uses POURBAIX calculation to deeply study the adsorption of other species on the catalyst surface at the working potential of carbon dioxide reduction, determines the full hydrogen adsorption on the molybdenum carbide surface, and designs a molybdenum carbide-loaded Rh single-atom catalyst that exhibits good performance in carbon dioxide reduction to produce methanol.

[0060] The present invention solves the technical problems in the prior art of high experimental research cost and great difficulty in improving the performance of preparing methanol by reducing carbon dioxide due to unclear reaction mechanism of transition metal-supported molybdenum carbide for preparing methanol by reducing carbon dioxide. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is a schematic diagram of the basic steps of a method for screening a catalyst for preparing methanol by reducing carbon dioxide according to Example 1 of the present invention;

[0062] Figure 2 Schematic diagram of specific steps for calculating the optimized structure (CONTCAR) and energy value (OUTCAR) of the TM@Mo2C model of Example 1 of the present invention;

[0063] Figure 3 This is a structural diagram of transition metal-loaded molybdenum carbide according to Example 1 of the present invention;

[0064] Figure 4 This is a schematic diagram of the formation energy of transition metal-supported molybdenum carbide according to Example 1 of the present invention;

[0065] Figure 5 is a POURBAIX diagram of molybdenum carbide according to Example 1 of the present invention;

[0066] Figure 6 This is a structural diagram of the transition metal-supported molybdenum carbide surface fully covered with hydrogen according to Example 1 of the present invention;

[0067] Figure 7 This is the free energy diagram of Rh@Mo2C in Example 1 of the present invention. DETAILED DESCRIPTION

[0068] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] Example 1

[0070] like Figure 1 As shown, the present invention provides a method for screening a catalyst for reducing carbon dioxide to prepare methanol, comprising the following basic steps:

[0071] S1. Calculate the optimized structure (CONTCAR) and energy value (OUTCAR) of the TM@Mo2C model;

[0072] like Figure 2 As shown, in this embodiment, the calculation process of the structure (CONTCAR) and energy value (OUTCAR) of the TM@Mo2C model after optimization also includes the following specific steps:

[0073] S11. Use Materials Studio to import the Mo2C.cif file in the Materials project structure library, cut the primitive cell using the Cleave Surfaces block, and set the Vacuum thickness option in Crystals-Build Vacuum Slab Crystal to Click Build to get the vacuum layer model, get the minimum unit molybdenum carbide structure, and convert it into an input file (POSCAR) that can be recognized by the VASP calculation software;

[0074] S12, structural optimization of molybdenum carbide materials;

[0075] In this embodiment, the input files required for calculation are set; in this embodiment, the input files include but are not limited to: INCAR, POSCAR, KPOINTS, POTCAR and scripts. Specifically, POTCAR can be implemented by, for example, the vaspkit-103 module; KPOINTS: select K-space grid points to calculate the integral in the Brillouin zone using the Gamma grid method, and the K point can be set to 2×2×1; INCAR: the interaction between electrons is described by the PBE functional under the generalized gradient approximation, and the valence band electron wave function uses the projected augmented plane wave pseudopotential basis set, and the energy convergence standard is 1×10 -5 eV, the force converges no more than The cutoff energy is 450eV, and other parameters are default values. The geometric structure of the molybdenum carbide material is optimized. After the calculation, the corresponding CONTCAR and OUTCAR files are obtained. The CONTCAR file can be imported using VESTA to visualize the structure and obtain structural information. The energy information of the OUTCAR file is extracted through VASP calculation. Subwork is a script.

[0076] S13, performing structural optimization and energy calculation on the minimum unit molybdenum carbide structure by VASP calculation software, and obtaining the optimized structure (CONTCAR) and energy value (OUTCAR);

[0077] S14, using Materials Studio and VESTA modeling software to expand the minimum unit of molybdenum carbide, and using VASP calculation software to perform structural optimization and energy calculation on the expanded molybdenum carbide; obtaining its optimized structure (CONTCAR) and energy value (OUTCAR);

[0078] In this embodiment, the aforementioned VESTA modeling software can expand the molybdenum carbide into small cells by (clicking Symmetry-Supercell) (2*2*1).

[0079] S15. Using Materials Studio and VESTA modeling software to construct the transition metal-loaded molybdenum carbide structure (TM@Mo2C) after the optimization (CONTCAR), and converting it into an input file (POSCAR) recognizable by the VASP calculation software;

[0080] In this embodiment, see Figure 1The structure of transition metal atoms loaded on molybdenum carbide (TM@Mo2C); TM is a transition metal element in the periodic table;

[0081] S16. Structural optimization and energy calculation of the constructed TM@Mo2C model were performed by VASP calculation software to obtain its optimized structure (CONTCAR) and energy value (OUTCAR);

[0082] S17. Repeat the above operation to obtain the optimized structure (CONTCAR) and energy value (OUTCAR) of the TM@Mo2C model.

[0083] S2. Calculation of the formation energy E of the TM@Mo2C model f ;

[0084] like Figure 2 As shown, in this embodiment, according to the formation energy calculation formula: E f =E(TM@Mo2C)-E(Mo2C)-u(TM), and the formation energy E of the TM@Mo2C model is calculated. f .

[0085] In this example, by comparing the E f The E value of the catalyst model was screened out. f Less than 0eV, that is, these transition metal atoms can exist stably when loaded on molybdenum carbide.

[0086] S3. Determine the coverage of other species of molybdenum carbide at the working potential under chemical reaction by calculating the POURBAIX diagram;

[0087] like Figure 3 As shown, in this embodiment, according to the POURBAIX diagram, the formulas are calculated as follows: Formula (1) and Formula (2); it is calculated that there is full hydrogen coverage on TM@Mo2C under chemical reaction.

[0088] *+mH2O→HnOm*+(2m-n)(H + +e - ) (1)

[0089] ΔG(U,pH)=G(HnOm*)-G(*)-mG(H2O)+(2m-n)[1 / 2G(H2)-eU SHE -kBTln(10)PH] (2)

[0090] like Figure 4 and Figure 6 As shown, in this embodiment, the TM@Mo2C with full hydrogen coverage on the surface is modeled using Materials Studio modeling software.

[0091] S4. The detailed electrocatalytic CO2RR and HER mechanisms of these catalysts were systematically explored through density functional theory (DFT) calculations.

[0092] In this example, with reference to previous studies, the elementary reactions of carbon dioxide reduction to produce methanol and the elementary reactions of hydrogen evolution reaction were determined:

[0093] a:*+CO2→*CO2

[0094] b:*CO2+H + +e - →*OCHO;

[0095] c:*OCHO+H + +e - → *HCOOH;

[0096] d:*HCOOH+H + +e - → *CHO+H2O;

[0097] e:*CHO+H + +e - →*OCH2;

[0098] f:*OCH2+H + +e - →*OCH3

[0099] g:*OCH3+H + +e - →*OHCH3

[0100] h:*OHCH3→*+CH3OH

[0101] i: *H+H + +e - →H2

[0102] In this embodiment, according to primitive operations, using Materials Studio, VESTA modeling software and VASP calculation software, the structures (CONTCAR) and energy data (OUTCAR) of the reactants and various intermediates in the carbon dioxide reduction reaction to prepare methanol and the hydrogen evolution reaction on the TM@Mo2C catalyst are calculated and optimized; catalysts showing high selectivity for CO2RR are selected through energy screening.

[0103] like Figure 5 and Figure 7 As shown, in this embodiment, the limiting potential is calculated by the formula: Gibbs free energy change (ΔG), that is:

[0104] ΔG=ΔE+ΔZPE-TΔS;UL =-ΔGmax / e

[0105] The free energy diagram of carbon dioxide reduction to methanol on TM@Mo2C catalyst was calculated to determine the performance of the catalyst. Finally, the limiting potential of Rh@Mo2C was obtained to be -0.22.

[0106] Example 2

[0107] In this example, the limiting potential of the Rh@Mo2C catalyst obtained by the present invention is used to compare the performance of the catalytic process of CO2RR using a copper catalyst.

[0108] In the operation of determining the limiting potential in this embodiment, the Gibbs free energy change (ΔG) is calculated, that is:

[0109] ΔG = ΔE + ΔZPE - TΔS;

[0110] Calculate the limiting potential (UL), which is:

[0111] U L =-ΔGmax / e.

[0112] The copper catalyst used for comparison in this example is considered to be one of the most effective CO2 reduction catalysts, which can selectively reduce carbon dioxide to methanol and other organic matter. The limiting potential required for the copper catalyst to carry out the carbon dioxide reduction reaction is between -0.5 and -1. The limiting potential of the Rh@Mo2C catalyst obtained in the present invention is -0.22, which significantly improves the performance of carbon dioxide reduction to prepare methanol.

[0113] In summary, the technical problem to be solved by the present invention is that the existing technology is unclear about the reaction mechanism of carbon dioxide reduction to prepare methanol in transition metal-loaded molybdenum carbide. The present invention provides theoretical guidance for experimental research, saves the trial and error cost and time of the experiment, and accelerates the research process of the experiment.

[0114] The present invention uses first-principles calculations to form a basis for judging the thermal stability of materials, thereby screening out transition metal-loaded molybdenum carbide materials with high stability.

[0115] The present invention calculates the POURBAIX diagram to obtain that the surface of transition metal-supported molybdenum carbide is fully covered with hydrogen under chemical reaction. Then, combined with the first principle, the performance of carbon dioxide reduction on the surface of transition metal-supported molybdenum carbide is calculated, and compared with the performance of carbon dioxide reduction on the copper surface, and the transition metal-supported molybdenum carbide material (Rh@Mo2C) with improved carbon dioxide reduction performance is screened out.

[0116] The present invention systematically studies the performance of preparing methanol by reducing carbon dioxide on transition metal-supported molybdenum carbide through first-principles calculations, and uses the method to obtain a material (Rh@Mo2C) with improved performance of preparing methanol by reducing carbon dioxide.

[0117] The present invention solves the technical problems in the prior art of high experimental research cost and great difficulty in improving the performance of preparing methanol by reducing carbon dioxide due to unclear reaction mechanism of transition metal-supported molybdenum carbide for preparing methanol by reducing carbon dioxide.

[0118] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for screening a catalyst for reducing carbon dioxide to produce methanol, characterized in that: The method comprises: S1, optimizing the TM@Mo2C model to obtain an applicable TM@Mo2C model, and calculating the optimized structure CONTCAR and energy value OUTCAR of the applicable TM@Mo2C model; S2. Calculate the formation energy E of the applicable TM@Mo2C model f , compare the formation energy E f to obtain a comparison result, and select a suitable catalyst model from the suitable TM@Mo2C model according to the comparison result; S3. According to the applicable catalyst model, a POURBAIX diagram is calculated to determine the coverage of other species of molybdenum carbide at a preset working potential under a preset chemical reaction, and a model is built for the coverage of other species using a preset modeling tool; S4. Calculate the electrocatalytic CO2RR mechanism information and HER mechanism information of each pre-set catalyst through density functional theory DFT, and determine the catalyst suitable for CO2RR.

2. A method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 1, characterized in that: The S1 includes: S11. Use the preset tools to import the Mo2C.cif file in the Materials project structure library, perform the primitive cell section operation through the CleaveSurfaces block, build the vacuum layer model, obtain and transform the minimum unit molybdenum carbide structure, and obtain the VASP-recognizable input file POSCAR; S12, setting an input file, performing structural optimization operation and energy calculation on the minimum unit molybdenum carbide structure through VASP calculation software, and obtaining the optimized structure CONTCAR and the energy value OUTCAR; S13, using a preset modeling tool, performing a cell expansion operation on the minimum unit molybdenum carbide structure to obtain expanded cell molybdenum carbide, and using the VASP calculation software to perform the structural optimization operation and the energy calculation on the expanded cell molybdenum carbide to obtain an expanded cell optimized structure CONTCAR and an expanded cell energy value OUTCAR; S14, constructing a transition metal-loaded molybdenum carbide structure TM@Mo2C for the expanded cell optimization structure CONTCAR, and converting the transition metal-loaded molybdenum carbide structure TM@Mo2C into the VASP-recognizable input file POSCAR to obtain the applicable TM@Mo2C model; S16, performing the structural optimization operation and the energy calculation on the applicable TM@Mo2C model by using VASP calculation software; S17, repeatedly executing S11 to S16 to obtain the optimized structure CONTCAR and the energy value OUTCAR.

3. A method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 2, characterized in that: In S12, the input files include: PBE functional description INCAR, the VASP recognizable input files POSCAR, KPOINTS, POTCAR and scripts.

4. The method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 2, characterized in that: The S12 further includes: S121. Optimize the geometric structure of the molybdenum carbide material and obtain a CONTCAR file and an OUTCAR file; S122, using VESTA to import the CONTCAR file and perform structural visualization processing to obtain structural information; S123, extracting energy information from the OUTCAR file through VASP calculation; S124. Use subwork as a script.

5. The method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 1, characterized in that: In S2, the formation energy E is obtained by using the following logic: f : E f =E(TM@Mo2C)-E(Mo2C)-u(TM)。 6. The method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 1, characterized in that: The S3 includes: S31. Calculate the POURBAIX diagram using the following reaction relationship: *+mH2O→HnOm*+(2m-n)(H + +e - ) ΔG(U,pH)=G(HnOm*)-G(*)-mG(H2O)+(2m-n)[1 / 2G(H2)-eU SHE -kBTln(10)PH] S32. Model the coverage of the remaining species using a preset modeling tool.

7. A method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 6, characterized in that: In S32, the preset modeling tool includes: Materials Studio modeling software.

8. The method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 1, characterized in that: In S4, according to the elementary operation, the carbon dioxide reduction to methanol production reaction and the hydrogen evolution reaction are optimized, and the optimized structures CONTCAR and the energy values ​​OUTCAR of the reactants and each intermediate on the TM@Mo2C catalyst are obtained through energy screening operation to obtain the catalyst suitable for CO2RR.

9. The method for screening a catalyst for preparing methanol by reducing carbon dioxide according to claim 1, characterized in that: The S4 includes: S41. Using the following logic, the limiting potential of the Rh@Mo2C catalyst is obtained: ΔG = ΔE + ΔZPE - TΔS; S42. Calculate the Gibbs free energy change ΔG using the following logic: UL=-ΔGmax / e.

10. A catalyst screening system for reducing carbon dioxide to produce methanol, characterized in that: The system comprises: A structure data and energy value acquisition module is used to optimize the TM@Mo2C model, obtain the applicable TM@Mo2C model, and calculate the optimized structure CONTCAR and energy value OUTCAR of the applicable TM@Mo2C model; Catalyst model screening module, used to calculate the formation energy E of the applicable TM@Mo2C model f , compare the formation energy E f to obtain a comparison result, and based on the comparison result, screen out a suitable catalyst model from the suitable TM@Mo2C model, wherein the catalyst model screening module is connected to the structural data and energy value acquisition module; A coverage modeling module, for calculating a POURBAIX diagram according to the applicable catalyst model, determining the coverage of other species of molybdenum carbide at a preset working potential under a preset chemical reaction, and using a preset modeling tool to model the coverage of the other species, wherein the coverage modeling module is connected to the catalyst model screening module; The catalyst determination module is used to calculate the electrocatalytic CO2RR mechanism information and HER mechanism information of each preset catalyst through density functional theory DFT, and determine the catalyst suitable for CO2RR accordingly. The catalyst determination module is connected to the coverage modeling module.

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