A method for precise design and efficient screening of diatomic catalysts based on MXenes and their application in CO2RR

Abstract

This invention discloses a method for the precise design and efficient screening of diatomic catalysts based on MXenes for CO2RR. The method includes the following steps: 1. Initial support selection; 2. Model construction; 3. Electronic structure screening; 4. Stability assessment; 5. Catalytic activity screening; 6. Selectivity screening. This invention uses first-principles calculations combined with high-throughput screening to identify diatomic combinations suitable for MXenes. Through electronic locality function analysis and calculations of formation and binding energies, stable MXene-based diatomic catalyst models are selected. Their thermodynamic stability is verified through molecular dynamics. Catalytic activity studies show that the rate-limiting step for Pd2-Mo2CO2 catalyzing NRR is as low as 0.23 eV, and the overpotential for Au2-Ti2CO2 catalyzing CO2RR to ethanol is only 0.6 V, demonstrating superior performance compared to traditional catalysts. This method provides an efficient catalyst design paradigm for electrochemical energy conversion.

Description

Technical Field

[0001] This invention belongs to the fields of computational materials science and catalysis technology, specifically relating to a method for the precise design and efficient screening of diatomic catalysts based on MXenes and their application in CO2RR. Background Technology

[0002] In the current field of electrochemical energy, the development of efficient catalysts is crucial for achieving sustainable energy utilization. Carbon dioxide electroreduction (CO2RR) can convert the greenhouse gas CO2 into valuable chemicals or fuels, representing an effective way to alleviate the energy crisis and reduce carbon emissions. Nitrogen reduction reaction (NRR) aims to convert nitrogen into ammonia, an important chemical raw material and potential energy carrier, whose synthesis process is significant for agriculture and the energy sector. Single-atom catalysts (SACs) have made some progress in catalysis, but they have limitations in terms of the flexibility of active sites and the loading capacity of metal atoms. Diatom catalysts (DACs), as an emerging research field, have the advantages of high metal atom loading and more flexible active sites, and are expected to overcome the shortcomings of SACs, playing a greater role in electrochemical energy conversion and storage.

[0003] MXenes, as a novel class of two-dimensional materials, possess excellent properties such as high conductivity, high specific surface area, and tunable surface functional groups, providing an ideal support platform for constructing high-performance catalysts. However, research on MXenes-based diatomic catalysts is still in its early stages, with many key issues remaining to be addressed. For example, how to screen suitable metal diatomic species and ensure their stable existence on MXenes supports, the unclear interaction mechanism between MXenes and diatoms, and how to precisely design MXenes-based diatomic catalysts to achieve efficient catalysis of reactions such as CO2RR and NRR, hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and CO oxidation. Existing catalyst development methods largely rely on extensive experimental trials, which are not only time-consuming, labor-intensive, and resource-intensive, but also have low development efficiency.

[0004] Therefore, developing a method for the design, screening, and application of MXenes-based diatomic catalysts based on a combination of theoretical calculations and experimental verification is of great scientific significance and practical application value for a deeper understanding of catalytic reaction mechanisms and for the rapid screening and design of high-performance catalysts. Summary of the Invention

[0005] The technical problem this invention aims to solve is to address the shortcomings of the existing technologies by providing a method for the precise design and efficient screening of diatomic catalysts based on MXenes for use in CO2RR. This method uses theoretical calculations to deeply study the electronic structure, stability, and catalytic activity of MXenes-based diatomic catalysts, screens high-performance catalysts, and reveals their catalytic mechanisms. This provides crucial support for related electrochemical energy conversion and storage technologies, and is particularly suitable for carbon dioxide electroreduction (CO2RR) and nitrogen reduction (NRR) reactions. It solves the problem of the difficulty in developing highly active and selective diatomic catalysts in existing technologies, thus promoting the development of related electrochemical energy conversion and storage technologies.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for the precise design and efficient screening of diatomic catalysts based on MXenes and their application in CO2RR, characterized in that the method includes the following steps:

[0007] Step 1: Initial selection of carriers: Select metal elements, then compare the atomic radius of the selected metal elements with the lattice parameters of MXenes to exclude MXenes carriers with lattice mismatch, and classify the MXenes carriers according to the lattice parameters to obtain the initial selection of MXenes carriers.

[0008] Step 2, Model Construction: Using the initially selected MXenes support obtained in Step 1, construct diatomic structures with Pt, Pd, and Au respectively. Complete the model construction and optimization by replacing the bulk metal atoms of the MXenes support to obtain the MXene-based diatomic catalyst model.

[0009] Step 3: Electronic structure screening: Calculate the electronic localization function of the MXene-based diatomic catalyst model obtained in Step 2, determine the existence state of the metal diatoms, and find that Pt, Pd and Au form metal bonds in the initially selected MXenes support and exist in diatomic form, thus obtaining a stable MXene-based diatomic catalyst model.

[0010] Step 4, Stability Assessment: Calculate the formation energy of the stable MXene-based diatomic catalyst model obtained in Step 3, eliminate unstable structures, then calculate the binding energy and transition state energy barrier of the remaining stable MXene-based diatomic catalyst models, and verify the structural stability by combining 300K molecular dynamics simulation to obtain the MXene-based diatomic catalyst that has passed the stability verification.

[0011] Step 5: Catalytic activity screening: Calculate the activation degree of the MXene-based diatomic catalyst obtained in Step 4 that has passed stability verification for the intermediate products of the catalytic reaction, and obtain the catalytic performance of the MXene-based diatomic catalyst;

[0012] Step 6: Selectivity Screening: Calculate the selectivity of the CO2RR catalyst in the MXene-based diatomic catalyst that has passed stability verification in Step 4, and obtain the MXene-based diatomic catalyst suitable for CO2RR.

[0013] This invention compares the atomic radius of doped metals with the lattice parameters of different MXenes to exclude MXenes unsuitable as substrate structures for DACs due to lattice mismatch. Suitable MXene samples are selected, and the variation law of lattice parameters in MXene structures is analyzed. It is found that for the same transition metal-based MXene, the lattice parameter increases with the increase of atomic layer number, period number, and group number. Based on these laws, a theoretical basis is provided for selecting suitable MXene supports. MXene supports are divided into three categories according to the size of lattice parameters. One sample is selected from each group to construct an MXene-based diatomic catalyst model. During the construction process, the doped metal diatoms directly replace the bulk transition metal atoms in the MXenes. The constructed structural model is fundamentally optimized using computational software to ensure the model's rationality and accuracy.

[0014] This invention employs computational materials science methods and software to calculate the electronic localization function (ELF) of an MXene-based diatomic catalyst model. It also performs cross-sectional analysis of the metal diatomic layer, determining the state of the metal diatoms within the MXene system based on the ELF diagram. Systems capable of forming stable metallic bonds and dimer structures are then selected. The invention concludes that when the atomic radius of the doped metal is smaller than that of Cu, the metal diatoms cannot form dimer structures in the MXene system. By calculating the ELF diagram, it is determined that metallic bonds can be formed in the MXene system, and the diatoms exist in dimer form, thus identifying stable MXene-based diatomic catalyst models.

[0015] This invention screens out the dimer formation energy of stable MXene-based diatomic catalyst models to preliminarily determine their stability. Further calculations are made of the binding energies of the single atom, dimer, and trimer of the remaining stable MXene-based diatomic catalyst models with the MXene substrate. Stability is evaluated from the perspective of binding energy, revealing a more stable MXene-based diatomic catalyst model for the dimer. This model not only forms the dimer but also avoids further cluster formation. The transition state (NEB) energy barrier for the MXene-based diatomic catalyst model's transformation to similar SACs or trimers is calculated. It is found that the NEB energy barrier for the transformation of similar MXene-based SACs and trimers to dimers is lower, while the energy barrier for the transformation of dimers to SACs and trimers is higher. The structural stability of the dimer in the remaining stable MXene-based diatomic catalyst models is verified from the perspective of reaction energy barriers. Furthermore, the structural stability is studied using molecular dynamics principles at an experimental temperature (300 K) with a cycling time of 4 ps, further corroborating the stability from a thermodynamic perspective. This comprehensively evaluates the stability of the MXene-based diatomic catalyst models.

[0016] This invention investigates the activation degree of common catalytic reaction intermediates of the screened MXene-based diatomic catalysts that have passed stability verification, evaluates their potential catalytic performance by calculating adsorption energy, obtains the catalytic performance of the MXene-based diatomic catalysts, and combines the selectivity of CO2RR catalysts to obtain MXene-based diatomic catalysts suitable for CO2RR.

[0017] The aforementioned method for precisely designing and efficiently screening diatomic catalysts based on MXenes for use in CO2RR is characterized in that the metal element mentioned in step one is Fe, Co, Ni, Mn, Cu, Zn, Rh, Ru, Ir, Pd, Pt, Ag, and Au. This invention determines the candidate diatomic metal types and screens MXenes supports by considering thirteen metals, including Fe, Co, Ni, Mn, Cu, Zn, Rh, Ru, Ir, Pd, Pt, Ag, and Au, as potential active sites for designing MXenes-based homonuclear metal diatomic catalysts.

[0018] The above-mentioned method for precise design and efficient screening of diatomic catalysts based on MXenes for use in CO2RR is characterized in that the initial MXenes support selected in step one is V2CO2, Nb2CO2, Mo2CO2, Ti2CO2 and W2CO2.

[0019] The above-described method for the precise design and efficient screening of diatomic catalysts based on MXenes for use in CO2RR is characterized in that the stable MXene-based diatomic catalyst model in step three is Pt2-V2CO2, Pt2-W2CO2, Pt2-Nb2CO2, Pd2-V2CO2, Pd2-W2CO2, Pd2-Mo2CO2, Au2-V2CO2, Au2-Nb2CO2, Au2-Mo2CO2, Au2-Ti2CO2, and Au2-W2CO2.

[0020] The above-described method for the precise design and efficient screening of diatomic catalysts based on MXenes for use in CO2RR is characterized in that, in step four, the unstable structures excluded include Pd2-W2CO2, Au2-W2CO2, and Au2-Mo2CO2, and the MXene-based diatomic catalysts that have passed stability verification are Pt2-V2CO2, Pt2-W2CO2, Pt2-Nb2CO2, Pd2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2.

[0021] The above-mentioned method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR is characterized in that the catalytic reaction in step five is HER, ORR, OER, CO oxidation, CO2RR and NRR.

[0022] The above-described method for precisely designing and efficiently screening diatomic catalysts based on MXenes for use in CO2RR is characterized in that the catalytic performance of the MXene-based diatomic catalysts in step five is as follows: Pt2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2 exhibit HER catalytic performance; Pt2-V2CO2 and Pt2-Nb2CO2 exhibit ORR catalytic performance; Au2-Ti2CO2 and Pt2-W2CO2 exhibit ORR and OER catalytic performance; Pt2-V2CO2 and Pd2-Mo2CO2 exhibit CO oxidation performance; Pt2-W2CO2 exhibits CRR catalytic performance; and Pt2-V2CO2, Pt2-W2CO2, Pd2-Mo2CO2, and Pd2-V2CO2 exhibit NRR catalytic performance.

[0023] The above-mentioned method for precise design and efficient screening of diatomic catalysts based on MXenes and their application in CO2RR is characterized in that the MXenes-based diatomic catalyst suitable for CO2RR in step six is ​​Au2-Ti2CO2.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. This invention conducts in-depth theoretical calculations to study the electronic structure, stability, and catalytic activity of MXenes-based diatomic catalysts, screens high-performance catalysts, and reveals their catalytic mechanisms, providing key support for related electrochemical energy conversion and storage technologies, especially applicable to CO2RR and NRR. The aim is to develop highly active and selective diatomic catalysts to promote the development of related electrochemical energy conversion and storage technologies.

[0026] 2. The method of the present invention based on MXenes for precise design and efficient screening of diatomic catalysts for CO2RR and NRR comprehensively utilizes first-principles calculations, high-throughput screening and machine learning techniques to construct a closed-loop R&D system of theoretical prediction and experimental verification.

[0027] 3. This invention systematically designs and screens MXenes-based diatomic catalysts by comprehensively applying a variety of theoretical calculation methods, avoiding the blindness of traditional experimental trial and error methods, greatly improving screening efficiency, and enabling the precise design of high-performance catalysts suitable for specific reactions.

[0028] 4. This invention delves into the interaction mechanism between MXenes and diatoms, including the relationship between electronic structure, stability, and catalytic activity, providing a theoretical basis for understanding the catalytic process of diatomic catalysts and contributing to further optimization of catalyst design.

[0029] 5. The high-performance MXenes-based diatomic catalysts screened in this invention exhibit excellent performance in important reactions such as CO2RR and NRR, and are expected to promote the development of related electrochemical energy conversion and storage technologies.

[0030] 6. The method proposed in this invention is not only applicable to the study of MXenes-based diatomic catalysts in CO2RR and NRR reactions, but can also be extended to other two-dimensional material-based catalysts and different types of catalytic reaction systems, providing new ideas and methods for the development of the entire catalysis field.

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0032] Figure 1 This is a schematic diagram illustrating the variation of lattice parameters of MXenes in this invention.

[0033] Figure 2 This is a schematic diagram of the sample structure of the MXenes-based diatomic catalyst model in this invention.

[0034] Figure 3 This is the ELF diagram of the MXene-based diatomic catalyst model in this invention.

[0035] Figure 4 This is an ELF diagram showing the doping of Pt, Pd, and Au bimetallic atoms in five MXenes systems: V2CO2, Nb2CO2, Mo2CO2, Ti2CO2, and W2CO2.

[0036] Figure 5 This represents the formation energy and binding energy with the MXene substrate of the stable MXene-based diatomic catalyst model in this invention.

[0037] Figure 6 This is a molecular dynamics stability diagram of the remaining stable MXene-based diatomic catalyst model in this invention.

[0038] Figure 7 This represents the adsorption energy of common catalytic reaction intermediates by the MXene-based diatomic catalyst, which has passed stability verification in this invention.

[0039] Figure 8 This is a Gibbs free energy pathway diagram of Pd2-V2CO2 and Pd2-Mo2CO2 as NRR catalysts in this invention.

[0040] Figure 9 This is a diagram showing the CO2RR pathway and reaction free energy step diagram for the conversion of CO2 to C2H4 on the Au2-Ti2CO2 surface in this invention. Detailed Implementation

[0041] Example 1

[0042] This embodiment includes the following steps:

[0043] Step 1: Initial Selection of Supports: Fe, Co, Ni, Mn, Cu, Zn, Rh, Ru, Ir, Pd, Pt, Ag, and Au are selected as metal elements. The atomic radii of the selected metal elements are then compared with the lattice parameters of MXenes to eliminate MXenes supports with lattice mismatches. The MXenes supports are further classified according to their lattice parameters to obtain the initially selected MXenes supports. The initially selected MXenes supports are V₂CO₂, Nb₂CO₂, Mo₂CO₂, Ti₂CO₂, and W₂CO₂. 2CO2; The metallic radii of all selected metal elements are larger than Cr2CO2 and smaller than Hf2CO2 and Zr2CO2. Therefore, considering the lattice mismatch problem, Cr2CO2, Hf2CO2, and Zr2CO2 are not suitable as the substrate structure for DACs. Subsequently, through classification and analysis of the lattice parameters of MXenes, it was found that for the same transition metal-based MXene, the lattice parameter increases with the number of atomic layers. Furthermore, the lattice parameter also increases with the number of periods and groups. See [link to relevant documentation]. Figure 1, This figure shows the variation of lattice parameters of different MXene systems. By analyzing this figure, it is possible to clearly see the rule that for the same transition metal-based MXene, as the number of atomic layers, periods, and groups increases, the lattice parameter increases. This provides a key basis for selecting a suitable MXene support, helps understand the influence of lattice parameters on the stability of dual-atom catalysts, and is an important reference for screening a suitable MXene support; the relevant rules of lattice parameters can be further summarized as follows: in the C-based MXene system without functional group modification, the lattice parameter sizes are arranged as Cr < W < Mo < V < Ta < Ti < Nb < Hf < Sc < Zr. In the N-based MXene system, the lattice parameter sizes are arranged as Cr < Mo < W < V < Ti < Ta < Nb < Hf < Sc < Zr. When modified with O functional groups, the lattice parameters of MXenes generally increase. And in the C-based MXene system, the lattice parameter sizes are arranged as Cr < V < Mo < W < Ti < Ta < Nb < Sc < Hf < Zr, while in the N-based MXene system, the lattice parameter sizes are arranged as Cr < W < Mo < V < Ti < Nb < Ta < Hf < Sc < Zr. If one wants to obtain stable MXene-based DACs, first, the bond length of the dimer should match the lattice of MXene; construct and optimize the MXene-based dual-atom catalyst model: divide MXenes into three categories according to the lattice parameter sizes, select one sample from each group, construct the sample structure of the MXene-based homonuclear dual-atom catalyst. During the construction process, the doped metal diatoms directly replace the bulk transition metal atoms in MXenes, and perform basic optimization on the structural model. Use V2CO2, Nb2CO2, Mo2CO2, Ti2CO2, and W2CO2 MXenes as supports to obtain the preliminary selected MXene supports;

[0044] Step 2. Model construction: Use the preliminary selected MXene supports obtained in Step 1 to construct dual-atom structures with Pt, Pd, and Au respectively. Complete the model construction and optimization by replacing the bulk metal atoms of the MXene supports to obtain the MXene-based dual-atom catalyst model; select 12 sample models from the dual-atom catalyst models composed of MXenes and metals for stability testing, as shown in Figure 2 , presenting the sample structures of the MXene-based dual-atom catalyst models selected in this study. These structures are constructed after considering factors such as lattice parameter matching. From Figure 2This provides a direct understanding of the position and distribution of doped metal diatoms in MXenes, laying the foundation for subsequent research on their electronic structure and catalytic performance. The sample structures of MXene-based homonuclear DACs selected for this study show that the doped metal DACs directly replace the bulk transition metal atoms in the MXenes, and basic structural model optimization was performed. Based on the optimized structural model, the electronic localization function (ELF) of these MXene-based diatomic catalyst models was further calculated, and a cross-sectional view of the metal diatomic layer was obtained. (See attached image) Figure 3 ELF plots can be used to analyze the existence state of metal diatoms in MXenes systems. The plots show that Co and Cu metal diatoms exist as isolated double monoatoms in some systems, thus revealing the relationship between atomic radius and dimer formation. This is an important basis for screening stable diatomic structures. Co and Cu metal diatoms exist as isolated double monoatoms in V₂CO₂, Nb₂CO₂, and Ta₄C₃O₂ systems. Therefore, when the atomic radius of a metal element is smaller than that of Cu, metal diatoms cannot form dimer structures in MXenes systems. In summary, since the lattice parameters of pre-transition metals are generally small, only the group with the largest bond lengths—Pt, Pd, and Au—can form metallic bonds and dimetallic dimer structures in Nb, V, Mo, Ti, and W-based MXenes systems with smaller lattice parameters.

[0045] Step 3: Electronic Structure Screening: Calculate the electronic localization function of the MXene-based diatomic catalyst model obtained in Step 2 to determine the existence state of the metal diatoms. It was found that Pt, Pd, and Au form metallic bonds and exist in diatomic form within the initially selected MXenes support, thus obtaining stable MXene-based diatomic catalyst models. These stable MXene-based diatomic catalyst models are Pt²⁻-V₂CO₂, Pt²⁻-W₂CO₂, Pt²⁻-Nb₂CO₂, Pd²⁻-V₂CO₂, and Pd²⁻-W₂CO₂. The possible MXene-based dimers were constructed using five M2XO2-type MXenes (V2CO2, Nb2CO2, Mo2CO2, Ti2CO2, and W2CO2) and doped with Pt, Pd, and Au. A total of 15 MXene-based dimers were then constructed, including Pd2-Mo2CO2, Au2-V2CO2, Au2-Nb2CO2, Au2-Mo2CO2, Ti2CO2, and W2CO2, and doped with Pt, Pd, and Au. The ELF diagrams of these 15 systems were then calculated. (See attached diagram). Figure 4The results showed that Pt diatoms could form metallic bonds in three MXene systems: V2CO2, W2CO2, and Nb2CO2; Pd could form metallic bonds in three MXene systems: V2CO2, W2CO2, and Mo2CO2; while Au could exist as a metallically bonded dimer in five MXene systems: V2CO2, Nb2CO2, Mo2CO2, Ti2CO2, W2CO2, and Nb2CO2. Stable MXene-based diatomic structures were screened out.

[0046] Step 4: Stability Assessment: Calculate the formation energy of the stable MXene-based diatomic catalyst model obtained in Step 3, eliminate unstable structures, then calculate the binding energy and transition state energy barrier of the remaining stable MXene-based diatomic catalyst models, and verify the structural stability using 300K molecular dynamics simulations to obtain MXene-based diatomic catalysts that have passed stability verification; the MXene-based diatomic catalysts that have passed stability verification are Pt2-V2CO2, Pt2-W2CO2, Pt2-Nb2CO2, Pd2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2; calculate the dimer formation energy of the screened possible MXene-based DACs, see... Figure 5 (a) shows the formation energy of dimer, which can be used to preliminarily determine its stability. Pd2-W2CO2, Au2-W2CO2, and Au2-Mo2CO2 are found to be unstable, while the remaining eight structures are preliminarily stable. Further calculations of the binding energies of these eight corresponding singleton, dimer, and trimer to the MXene substrate are shown in [reference needed]. Figure 5 (b) This study comprehensively assesses the stability of diatomic catalysts, providing data support for further screening of stable diatomic structures. It was found that, except for Au2-V2CO2 and Au2-Nb2CO2, the dimers of the remaining stable MXene-based diatomic catalyst models are more stable, indicating that they can not only form dimers but also avoid further cluster formation. The transition state energy barriers for the remaining stable MXene-based diatomic catalyst models to transform into similar SACs or trimers were calculated. It was found that the NEB energy barriers for the transformation from MXene-based SACs and trimers to dimers are low, both less than 0.35 eV, while the energy barriers for the transformation from dimers to SACs and trimers are high, both above 0.75 eV. This verifies the structural stability of the remaining stable MXene-based diatomic catalyst models from the perspective of reaction energy barriers. Furthermore, the structural stability of the remaining stable MXene-based diatomic catalyst models under 4 ps cycling at the experimental temperature (300 K) was studied using molecular dynamics principles. (See [link to study]). Figure 6 The results showed that none of their structures underwent significant distortion, further corroborating their stability from a thermodynamic perspective;

[0047] Step 5: Catalytic Activity Screening: Calculate the activation degree of the MXene-based diatomic catalyst obtained in Step 4 (which has passed stability verification) on intermediate products of catalytic reactions to obtain the catalytic performance of the MXene-based diatomic catalyst; investigate the activation degree of the MXene-based diatomic catalyst (which has passed stability verification) on intermediate products of common catalytic reactions (including ORR, OER, HER, CO oxidation, CO2RR, and NRR), and evaluate its potential catalytic performance by calculating the adsorption energy. See [link to relevant documentation]. Figure 7 This figure shows the adsorption energies of MXene-based diatomic catalysts for various common catalytic reaction intermediates, which have passed stability verification. By analyzing the magnitude of the adsorption energy, the potential catalytic performance of the catalysts for different reactions can be evaluated, thereby screening for catalysts with high activity in specific reactions (such as HER, CO2RR, and NRR). This is an important reference for studying catalyst activity. It was found that Pt2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2 have potential catalytic performance for HER, while Pt2-V2CO2 and Pt2-Nb2CO2... This study focuses on three reactions: HER, CO2RR, and NRR, using ORR (Oriented Reaction-Oriented Reactions). HER performance was assessed by calculating the Gibbs free energy. Pt2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2 showed the highest activity, with Pt2-V2CO2 exhibiting a negative free energy and being closest to the equilibrium potential. However, this characteristic makes it unfavorable for CO2RR and NRR reactions. In the NRR study, two Pd-based catalysts (Pd2-V2CO2 and Pd2-Mo2CO2) were selected as research subjects, and the Gibbs free energy of the NRR reaction was calculated. (See attached data). Figure 8 The rate-limiting steps were found to be 0.29 eV and 0.23 eV, respectively, which is better than the previously published case using Ti3C2O2 boundary sites as catalysts;

[0048] Step Six: Selectivity Screening: The selectivity of the CO2RR catalyst among the MXene-based diatomic catalysts obtained in Step Four (which passed stability verification) was calculated to obtain MXene-based diatomic catalysts suitable for CO2RR. The selectivity of four CO2RR catalysts was tested. It was found that, except for Ti2CO2-Au2, the free energy of the other three MXene-based homonuclear dimer catalysts for forming CO-CO coupling products was very high, indicating that they did not have the catalytic ability to generate C2 products. Ti2CO2-Au2, however, showed high selectivity for CO2RR to C2 products. (See...) Figure 9 Its overpotential for catalytic conversion to ethanol is only 0.6 eV, which is higher than that of currently commercially available copper-based catalysts. The MXenes-based diatomic catalyst suitable for CO2RR is Au2-Ti2CO2.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method for the precise design and efficient screening of diatomic catalysts based on MXenes and their application in CO2RR, characterized in that, The method includes the following steps: Step 1: Initial selection of carriers: Select metal elements, then compare the atomic radius of the selected metal elements with the lattice parameters of MXenes to exclude MXenes carriers with lattice mismatch, and classify the MXenes carriers according to the lattice parameters to obtain the initial selection of MXenes carriers. Step 2, Model Construction: Using the initially selected MXenes support obtained in Step 1, construct diatomic structures with Pt, Pd, and Au respectively. Complete the model construction and optimization by replacing the bulk metal atoms of the MXenes support to obtain the MXene-based diatomic catalyst model. Step 3: Electronic structure screening: Calculate the electronic localization function of the MXene-based diatomic catalyst model obtained in Step 2, determine the existence state of the metal diatoms, and find that Pt, Pd and Au form metal bonds in the initially selected MXenes support and exist in diatomic form, thus obtaining a stable MXene-based diatomic catalyst model. Step 4, Stability Assessment: Calculate the formation energy of the stable MXene-based diatomic catalyst model obtained in Step 3, eliminate unstable structures, then calculate the binding energy and transition state energy barrier of the remaining stable MXene-based diatomic catalyst models, and verify the structural stability by combining 300K molecular dynamics simulation to obtain the MXene-based diatomic catalyst that has passed the stability verification. Step 5: Catalytic activity screening: Calculate the activation degree of the MXene-based diatomic catalyst obtained in Step 4 that has passed stability verification for the intermediate products of the catalytic reaction, and obtain the catalytic performance of the MXene-based diatomic catalyst; Step 6: Selectivity Screening: Calculate the selectivity of the CO2RR catalyst in the MXene-based diatomic catalyst that has passed stability verification in Step 4, and obtain the MXene-based diatomic catalyst suitable for CO2RR.

2. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 1, characterized in that, The metallic elements mentioned in step one are Fe, Co, Ni, Mn, Cu, Zn, Rh, Ru, Ir, Pd, Pt, Ag, and Au.

3. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 2, characterized in that, The initial MXenes carriers selected in step one are V2CO2, Nb2CO2, Mo2CO2, Ti2CO2 and W2CO2.

4. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 3, characterized in that, The stable MXene-based diatomic catalyst models mentioned in step three are Pt2-V2CO2, Pt2-W2CO2, Pt2-Nb2CO2, Pd2-V2CO2, Pd2-W2CO2, Pd2-Mo2CO2, Au2-V2CO2, Au2-Nb2CO2, Au2-Mo2CO2, Au2-Ti2CO2, and Au2-W2CO2.

5. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 4, characterized in that, In step four, the unstable structures excluded include Pd2-W2CO2, Au2-W2CO2, and Au2-Mo2CO2. The MXene-based diatomic catalysts that passed stability verification are Pt2-V2CO2, Pt2-W2CO2, Pt2-Nb2CO2, Pd2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2.

6. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 5, characterized in that, The catalytic reactions described in step five are HER, ORR, OER, CO oxidation, CO2RR, and NRR.

7. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 6, characterized in that, The catalytic performance of the MXene-based diatomic catalysts mentioned in step five is as follows: Pt2-V2CO2, Pd2-Mo2CO2, and Au2-Ti2CO2 exhibit HER catalytic performance; Pt2-V2CO2 and Pt2-Nb2CO2 exhibit ORR catalytic performance; Au2-Ti2CO2 and Pt2-W2CO2 exhibit ORR and OER catalytic performance; Pt2-V2CO2 and Pd2-Mo2CO2 exhibit CO oxidation performance; Pt2-W2CO2 exhibits CRR catalytic performance; and Pt2-V2CO2, Pt2-W2CO2, Pd2-Mo2CO2, and Pd2-V2CO2 exhibit NRR catalytic performance.

8. The method for precise design and efficient screening of diatomic catalysts based on MXenes and used for CO2RR according to claim 6, characterized in that, The MXenes-based diatomic catalyst suitable for CO2RR mentioned in step six is ​​Au2-Ti2CO2.

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