A transition metal single-atom supported C6N3 two-dimensional material catalyst screening method and system

Abstract

The present application relates to the technical field of electrocatalytic material design, and particularly relates to a transition metal monatomic supported C6N3 two-dimensional material catalyst screening method and system, and its technical points are: a periodic structure model of two-dimensional material C6N3 is constructed; transition metal atoms are introduced at the nitrogen-rich pore sites to form a TM-C6N3 catalyst model; the TM-C6N3 catalyst model is subjected to structure optimization and the binding energy between the transition metal atoms and the C6N3 substrate is calculated, and TM-C6N3 catalyst stable configurations with binding energy less than 0 are screened out; the adsorption free energy of O2 and N2 on the transition metal sites on the surface of the TM-C6N3 catalyst stable configuration is calculated respectively, and the TM-C6N3 catalyst stable configuration is preliminarily screened according to the comparison between the adsorption free energy and the screening threshold to obtain a candidate catalyst set; and then the catalytic performance evaluation of ORR and NRR is performed to obtain catalysts suitable for ORR and NRR.

Description

Technical Field

[0001] This invention relates to the field of electrocatalytic material design technology, specifically to a catalyst screening method and system for a two-dimensional C6N3 material supported by a single transition metal atom. Background Technology

[0002] With the increasing demands for energy structure transformation and sustainable development, efficient and clean energy conversion and chemical synthesis technologies have received widespread attention. In electrochemical energy systems, the oxygen reduction reaction (ORR) is a key cathode reaction in devices such as fuel cells and metal-air batteries. Its reaction involves multi-electron and multi-proton coupling transfer, and its kinetics are inherently slow, often becoming a critical step limiting the overall efficiency of the device. On the other hand, the electrocatalytic nitrogen reduction reaction (NRR) provides a potential pathway for the green synthesis of ammonia under mild conditions. However, due to the high bond energy and low chemical reactivity of nitrogen molecules, its adsorption and stepwise hydrogenation processes face significant reaction energy barriers and are also susceptible to competition from side reactions, leading to limited reaction selectivity.

[0003] To address the aforementioned issues, extensive research has been conducted on ORR and NRR catalysts in existing technologies. Catalytic materials, particularly noble metals and their alloys, exhibit high catalytic activity, but are costly and resource-constrained. To improve the utilization efficiency of metal atoms and regulate the electronic structure of reactive sites, researchers have gradually introduced the design concept of single-atom catalysts. By anchoring transition metal atoms in single-atom form on the surface or pores of two-dimensional materials, precise control of catalytic performance can be achieved. Furthermore, computational simulation-based material design methods have been used to analyze the structural stability of catalysts, reactant adsorption behavior, and reaction pathway characteristics, thus improving the efficiency of catalyst screening to some extent.

[0004] However, existing catalyst design and screening methods typically focus on single-reaction systems of ORR or NRR, lacking a unified design framework for multi-reaction systems. Furthermore, for two-dimensional materials supported by transition metal single atoms, their configuration types, adsorption behaviors, and reaction pathways vary significantly. Existing studies largely rely on empirical analysis of individual systems, and a systematic, reproducible screening process and evaluation criteria have not yet been established. Particularly for nitrogen-rich two-dimensional framework materials such as C6N3, further refinement is needed to develop catalyst design methods that consider both ORR and NRR around transition metal single-atom sites.

[0005] Therefore, it is necessary to propose a screening method for ORR / NRR catalysts of C6N3 two-dimensional materials supported by single atoms of transition metals, so as to achieve efficient screening and performance evaluation of candidate catalysts. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides a catalyst screening method and system for C6N3 two-dimensional materials supported by a single atom of a transition metal. This method effectively solves the problem of the lack of a unified, efficient, and rationally designed method that takes into account both bifunctional catalytic performance when screening single-atom catalysts suitable for oxygen reduction reaction (ORR) and electrocatalytic nitrogen reduction reaction (NRR).

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides a catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material, the method comprising:

[0009] S1. Construct a periodic structural model of the two-dimensional material C6N3;

[0010] S2. Transition metal atoms are introduced into the nitrogen-rich pore sites of the periodic structure model to form a TM-C6N3 catalyst model supported by transition metal atoms.

[0011] S3. Optimize the structure of the TM-C6N3 catalyst model and calculate the binding energy between the transition metal atoms and the C6N3 substrate. Select stable configurations of the TM-C6N3 catalyst with binding energies less than 0.

[0012] S4. Calculate the adsorption free energies of the target reactant molecules O2 and N2 at the transition metal sites on the surface of the stable configuration of the TM-C6N3 catalyst, and perform preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the adsorption free energies to obtain a set of candidate catalysts.

[0013] S5. Evaluate the catalytic performance of the candidate catalyst set for oxygen reduction reaction and nitrogen reduction reaction to obtain a TM-C6N3 catalyst suitable for oxygen reduction reaction and electrocatalytic nitrogen reduction reaction.

[0014] Furthermore, in step S2, the transition metal single atom is selected from at least one of 3d, 4d, or 5d transition metal elements.

[0015] Furthermore, in step S3, the binding energy Ebind between the transition metal single atom and the C6N3 substrate is calculated according to the following formula:

[0016] ;

[0017] in, This represents the total energy of the C6N3 catalyst system supported by a single transition metal atom. For the energy of the C6N3 substrate, This represents the energy of an isolated transition metal atom.

[0018] Furthermore, in step S4, the preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the adsorption free energy includes the following steps:

[0019] The stable configuration of the TM-C6N3 catalyst with adsorption free energies of O2 and N2 both less than 0 eV was retained to obtain the candidate catalyst set.

[0020] Furthermore, the adsorption free energy ΔGads of the target reactant molecules on the surface of the TM-C6N3 catalyst is calculated according to the following relationship:

[0021] ;

[0022] Where ΔEads is the energy change of the system before and after reactant molecule adsorption, ΔEzpe is the zero-point energy correction term, T is the temperature, and ΔS is the entropy change.

[0023] Furthermore, the evaluation of the catalytic performance of the oxygen reduction reaction includes:

[0024] A multi-electron reaction pathway model for the oxygen reduction reaction was constructed, and the free energy changes of each elementary reaction step in the oxygen reduction reaction pathway were calculated using a hydrogen electrode model.

[0025] The step corresponding to the maximum value of the free energy change of the oxygen reduction reaction is regarded as the potential limiting step of the oxygen reduction reaction.

[0026] Calculate the theoretical overpotential of the oxygen reduction reaction corresponding to the potential limiting step of the oxygen reduction reaction, and evaluate the catalytic activity of the oxygen reduction reaction based on the theoretical overpotential.

[0027] Furthermore, when the theoretical overpotential of the oxygen reduction reaction is less than 0.7 V, the catalyst is determined to have good ORR activity.

[0028] Furthermore, the free energy changes of each elementary reaction step in the oxygen reduction reaction. The theoretical overpotential was evaluated based on the calculated hydrogen electrode model. Defined as:

[0029] ;

[0030] in, This is the theoretical overpotential for the oxygen reduction reaction; This represents the free energy changes of each elementary reaction step in the oxygen reduction reaction; is the free energy change value corresponding to the reaction step with the largest free energy change in the ORR reaction pathway, e is the charge of the electron, and 1.23 V is the standard equilibrium potential of ORR.

[0031] Furthermore, the evaluation of the catalytic performance of the electrocatalytic nitrogen reduction reaction includes:

[0032] A stepwise protonation reaction pathway model was constructed, and the free energy changes at each reaction step were calculated.

[0033] The step corresponding to the maximum value of the free energy change of the electrocatalytic nitrogen reduction reaction is regarded as the potential limiting step of the electrocatalytic nitrogen reduction reaction.

[0034] Calculate the theoretical overpotential of the electrocatalytic nitrogen reduction reaction corresponding to the potential limiting step of the electrocatalytic nitrogen reduction reaction, and evaluate the catalytic activity of the electrocatalytic nitrogen reduction reaction based on the theoretical overpotential.

[0035] Furthermore, when the theoretical overpotential of the electrocatalytic nitrogen reduction reaction is less than 0.5 V, the catalyst is determined to have excellent NRR activity.

[0036] Furthermore, when the theoretical overpotential is less than 0.3 V, it is determined to have excellent catalytic potential.

[0037] Furthermore, the free energy changes of each stepwise protonation reaction in the electrocatalytic nitrogen reduction reaction. The theoretical overpotential, obtained through reaction pathway analysis, is determined according to the following relationship:

[0038] ;

[0039] in, This is the theoretical overpotential for the electrocatalytic nitrogen reduction reaction; The free energy changes of each step protonation reaction in the electrocatalytic nitrogen reduction reaction; denoted as , where is the free energy change value corresponding to the reaction step with the largest free energy change in the NRR reaction pathway, e is the charge of an electron, and Ueq is the equilibrium potential of the NRR reaction, representing the theoretical potential required to drive the conversion of N2 to NH3 under thermodynamic equilibrium conditions.

[0040] Furthermore, the evaluation of the catalytic performance of the electrocatalytic nitrogen reduction reaction also includes: analyzing the relationship between the free energy of key free bodies and the descriptor during the electrocatalytic nitrogen reduction reaction, in order to help screen catalysts with better electrocatalytic nitrogen reduction catalytic potential.

[0041] Secondly, this invention also provides a catalyst screening system for C6N3 two-dimensional materials supported by a single atom of a transition metal, comprising: a model building module, a binding stabilization module, a preliminary screening module, and a performance evaluation module.

[0042] The model building module is used to construct a periodic structure model of the two-dimensional material C6N3; transition metal atoms are introduced at the nitrogen-rich pore sites of the periodic structure model to form a TM-C6N3 catalyst model supported by transition metal atoms.

[0043] The binding stabilization module is used to optimize the structure of the TM-C6N3 catalyst model, calculate the binding energy between transition metal atoms and the C6N3 substrate, and screen out stable configurations of the TM-C6N3 catalyst with binding energies all less than 0.

[0044] The preliminary screening module is used to calculate the adsorption free energies of target reactant molecules O2 and N2 at the transition metal sites on the surface of the stable configuration of the TM-C6N3 catalyst, and to perform preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the comparison between the adsorption free energies and the screening threshold, thereby obtaining a set of candidate catalysts.

[0045] The performance evaluation module is used to evaluate the catalytic performance of the candidate catalyst set for oxygen reduction reaction and nitrogen reduction reaction, so as to obtain a TM-C6N3 catalyst suitable for oxygen reduction reaction and electrocatalytic nitrogen reduction reaction.

[0046] Thirdly, the present invention also provides an electronic device, comprising:

[0047] Memory, used to store computer programs;

[0048] When the processor executes the computer program stored in the memory, it implements the steps of the catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material as described in the first aspect.

[0049] The technical solution provided by this invention has the following advantages compared with the known prior art:

[0050] 1. This invention provides a unified catalyst screening method for dual-functional requirements of oxygen reduction reaction (ORR) and electrocatalytic nitrogen reduction reaction (NRR). Through an integrated process of configuration construction, stability anchoring screening, adsorption behavior screening, and dual-path reaction performance evaluation, it realizes a systematic, reproducible, and efficient screening of the catalytic performance of transition metal single-atom supported C6N3 two-dimensional materials in ORR / NRR, overcoming the shortcomings of existing technologies that are designed for single reactions and lack a general evaluation framework.

[0051] 2. This invention uses adsorption free energy, reaction pathway free energy changes, potential limiting steps, and theoretical overpotential as evaluation criteria to achieve a systematic comparison and screening of the catalytic performance of TM-C6N3 catalysts in ORR and NRR. By constructing ORR multi-electron transfer pathways and NRR stepwise protonation pathways respectively, and identifying limiting steps and calculating theoretical overpotentials based on free energy changes, the accuracy and comparability of catalyst activity prediction are significantly improved.

[0052] 3. This invention is applicable to TM-C6N3 systems with different transition metal single-atom supports, which can improve the efficiency of candidate catalyst screening and performance evaluation, and provide methodological support for the rational design of ORR / NRR catalysts;

[0053] 4. This invention reveals the intrinsic law between the electronic properties of the metal center and the NRR catalytic potential in the TM-C6N3 system by introducing correlation analysis between the free energy of key intermediates and electronic structure descriptors (such as φ), and provides theoretical guidance for the rational design of highly active NRR catalysts.

[0054] 5. The screening method of the present invention is modular and can be deployed in electronic devices, supporting automated, high-throughput virtual screening of catalysts, significantly reducing experimental trial and error costs, and accelerating the research and development process of novel bifunctional electrocatalysts. Attached Figure Description

[0055] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0056] Figure 1 This is a schematic diagram of the overall process for designing ORR / NRR catalysts of C6N3 two-dimensional materials supported by a single atom of transition metal in this invention.

[0057] Figure 2 This is a schematic diagram of the structural model of the transition metal single-atom supported C6N3 two-dimensional material (TM-C6N3) catalyst in an embodiment of the present invention;

[0058] Figure 3 This is a schematic diagram of the adsorption free energy of the target reactant molecules on the surface of the TM-C6N3 catalyst in an embodiment of the present invention, wherein (a) is the adsorption free energy diagram of O2 molecules on the surface of the TM-C6N3 catalyst, and (b) is the adsorption free energy diagram of N2 molecules on the surface of the TM-C6N3 catalyst.

[0059] Figure 4This is a key oxygen-containing intermediate for the oxygen reduction reaction on a transition metal single-atom supported C6N3 two-dimensional material (TM-C6N3) catalyst in the embodiments of the present invention. O、 OOH and A schematic diagram of the adsorption free energy of OH and its scaling relationships, where (a) is... OH adsorption free energy and A schematic diagram of the scaling relationship between O adsorption free energies is shown in (b). OH adsorption free energy and Schematic diagram of the scaling relationship between the adsorption free energies of OOH;

[0060] Figure 5 This is a schematic diagram of the oxygen reduction reaction (ORR) performance evaluation of the TM-C6N3 catalyst in the embodiments of the present invention. (a) is a schematic diagram of the volcano relationship between the theoretical overpotential of ORR and the adsorption free energy of *OH. (b) is a schematic diagram of the correlation between the descriptor φ and the theoretical overpotential of ORR. (c) and (d) are schematic diagrams of the free energy changes of the ORR reaction pathway of typical TM-C6N3 catalysts (Cu-C6N3 and Ag-C6N3) obtained by screening under different potential conditions.

[0061] Figure 6 This is a schematic diagram of the free energy changes of key reaction steps in the electrocatalytic nitrogen reduction reaction (NRR) of the TM-C6N3 catalyst in the embodiments of the present invention, wherein (a) is the initial hydrogenation step of N2 at different transition metal single atom sites ( N2→ (b) is the change in free energy corresponding to N2H, and (c) is the change in free energy of the terminal hydrogenation step (N2H). NH2→ The change in free energy corresponding to NH3;

[0062] Figure 7 This is a schematic diagram illustrating the relationship between the free energy of a key intermediate and the descriptor φ during the NRR reaction process in an embodiment of the present invention, wherein (a) is... The relationship between the free energy of N2H and the descriptor φ is shown in (b). N2H and A linear relationship between the free energies of NH2;

[0063] Figure 8 The figures show the free energy changes of typical TM-C6N3 catalysts screened in the embodiments of the present invention under different reaction pathways in the electrocatalytic nitrogen reduction reaction (NRR), where (a) is the free energy diagram of Ru-C6N3 under different reaction pathways in the NRR reaction, and (b) is the free energy diagram of Pt-C6N3 under different pathways in the NRR reaction. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0065] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail. The terms “comprising,” “including,” “having,” “containing,” etc., as used herein are open-ended terms, meaning that they include but are not limited to. Unless the context clearly indicates otherwise, the expressions “a” and “an” as used herein include plural references. It should be noted that “first,” “second,” etc., are used merely for convenience of description and distinction and should not be construed as indicating or implying relative importance. The term “about” as used herein indicates a range of ±20% of the following numerical value. In some embodiments, the term “about” indicates a range of ±10% of the following numerical value. In some embodiments, the term “about” indicates a range of ±5% of the following numerical value. The invention is further described below with reference to embodiments.

[0066] This invention provides a method and system for screening catalysts using C6N3 two-dimensional materials supported by a single atom of a transition metal. It effectively solves the problem that existing technologies lack a unified, efficient screening method that takes into account both bifunctional catalytic performance when screening single-atom catalysts suitable for oxygen reduction reaction (ORR) and electrocatalytic nitrogen reduction reaction (NRR).

[0067] Example: Refer to Figures 1 to 8 .

[0068] Depend on Figure 1 It can be seen that the overall screening process includes steps such as catalyst model construction, stability screening, reactant adsorption behavior analysis, and catalytic performance evaluation based on reaction pathway.

[0069] First, a periodic structural model of the two-dimensional C6N3 material was constructed, and at least one transition metal atom was introduced into its intrinsic nitrogen-rich pore sites to form a TM-C6N3 catalyst model supported by a single transition metal atom. A schematic diagram of the TM-C6N3 catalyst model structure is shown below. Figure 2 As shown. The structure of the TM-C6N3 catalyst model was optimized, and the binding energy between the transition metal single atom and the C6N3 substrate was calculated. The calculation formula is as follows:

[0070] ;

[0071] in, This represents the total energy of the C6N3 catalyst system supported by a single transition metal atom. Ebind represents the binding energy of the C6N3 substrate, and ETM represents the energy of an isolated transition metal atom. The results show that the binding energy of all TM-C6N3 systems is negative (Ebind < 0), indicating that the anchoring of transition metal single atoms at nitrogen-rich pore sites in C6N3 is thermodynamically favorable. Further comparison of the binding energies of different transition metal single atoms reveals that most 3d, 4d, and 5d transition metal systems exhibit larger absolute values ​​of binding energy, reflecting stronger metal-support interactions; while some later-group transition metal systems have relatively smaller absolute values ​​of binding energy, indicating relatively weaker single-atom anchoring capabilities.

[0072] After obtaining a stable TM-C6N3 catalyst model, the adsorption free energy of the target reactant molecules on the catalyst surface was further calculated using the following formula:

[0073] ;

[0074] Where ΔEads is the energy change of the system before and after reactant molecule adsorption, ΔEzpe is the zero-point energy correction term, T is the temperature, and ΔS is the entropy change. The calculation results are as follows: Figure 3 As shown. Targeting the oxygen reduction reaction (ORR) and electrocatalytic nitrogen reduction reaction (NRR), the adsorption free energies of O2 and N2 molecules at the transition metal single-atom sites were calculated, respectively. Both O2 and N2 adsorption free energies should be less than 0 eV to proceed to the next activation reaction; a larger negative value indicates a better activation effect. For the ORR process, the adsorption energy of O2 in each TM-C6N3 system (…) The adsorption free energy of O2 molecules ranges from -0.04 eV to -3.47 eV, indicating that the adsorption of O2 molecules on transition metal single-atom sites is generally energy-favorable. Further comparison of different transition metal systems reveals significant differences in the adsorption capacity of different metal centers for O2 molecules. Some early transition metal systems exhibit relatively strong O2 adsorption, while later transition metal systems (such as Ag and Au) show relatively weaker O2 adsorption. Considering that the adsorption strength of reactants in the ORR reaction is usually moderate, excessively strong or weak O2 adsorption may be detrimental to the formation and transformation of key intermediates. Therefore, the O2 adsorption free energy is used as one of the important criteria for the initial screening of TM-C6N3 catalysts. For the NRR process, the adsorption free energy of N2 molecules on the surface of the TM-C6N3 catalyst was further calculated, and the values ​​also showed significant differences among different transition metal single-atom systems. Some transition metal single-atom sites showed weak adsorption capacity for N2 molecules, while others were able to form relatively stable adsorption configurations at the metal centers. Considering that the effective adsorption of N2 molecules in the NRR reaction is a prerequisite for the subsequent stepwise hydrogenation reaction, 0.6 eV was used as the adsorption free energy screening threshold to exclude the TM-C6N3 catalyst system with insufficient N2 adsorption capacity, thereby obtaining a set of candidate catalysts for subsequent NRR reaction pathway analysis.

[0075] Based on this, a multi-electron reaction pathway model for the oxygen reduction reaction (ORR) was constructed, focusing on key oxygen-containing intermediates in the reaction process. OOH, O and The reaction steps of OH were analyzed. The free energy changes of each elementary reaction step were calculated to obtain the free energy changes of the ORR reaction pathway on the TM-C6N3 catalyst. The free energy changes ΔGi of each elementary reaction step of the oxygen reduction reaction were evaluated according to the calculated hydrogen electrode model, and its theoretical overpotential ηORR was defined as:

[0076] ;

[0077] Where max(ΔGi) is the free energy change corresponding to the reaction step with the largest free energy change in the ORR reaction pathway, e is the charge of an electron, and 1.23V is the standard equilibrium potential of ORR. The scaling relationships between its key intermediates are as follows: Figure 4 As shown. Further, based on the elementary reaction steps with the largest free energy changes in the ORR reaction pathway, the corresponding potential limiting steps are determined, and the corresponding theoretical overpotentials are calculated. The theoretical overpotentials of ORR for different TM-C6N3 catalysts are compared with... The volcanic relationship between OH adsorption free energy and its correlation with the descriptor φ are as follows: Figure 5As shown in (a) and (b) in the example, taking a portion of the TM-C6N3 catalyst in the implementation example as an example, the Cu-C6N3 and Ag-C6N3 systems are in a relatively favorable position in the volcanic relationship, with corresponding theoretical ORR overpotentials of 0.69 V and 0.65 V, respectively. The changes in their reaction pathway free energy are shown in the figure. Figure 5 As shown in (c) and (d) above. Simultaneously, on the same TM-C6N3 catalyst system, a stepwise protonation reaction pathway was constructed for the electrocatalytic nitrogen reduction reaction, and the free energy changes of each reaction step were analyzed. The free energy changes ΔGj of each stepwise protonation reaction step in the electrocatalytic nitrogen reduction reaction were obtained through reaction pathway analysis, and their limiting potential Ulim or theoretical overpotential was determined according to the following relationship:

[0078] ;

[0079] Where max(ΔGj) is the free energy change value corresponding to the reaction step with the largest free energy change in the NRR reaction pathway, e is the charge of the electron, and Ueq is the equilibrium potential of the NRR reaction, representing the theoretical potential required to drive the conversion of N2 to NH3 under thermodynamic equilibrium conditions. Initial hydrogenation steps of N2 at different transition metal single-atom sites ( N2→ N2H) and the terminal hydrogenation step ( NH2→ The change in free energy of NH3 is as follows: Figure 6 As shown, this is used to identify potential limiting steps in the NRR reaction. Furthermore, the relationship between the free energy of key intermediates and the descriptor φ during the NRR reaction is analyzed, and the results are as follows: Figure 7 As shown, this study aims to assist in screening TM-C6N3 catalysts with superior NRR catalytic potential. Based on this, representative TM-C6N3 catalysts were selected, and their NRR reaction processes under different reaction pathways were further analyzed. The changes in the reaction pathway free energy are shown in the figure. Figure 8 As shown. By comparing the free energy changes of each reaction step in the continuous hydrogenation pathway and the enzymatic hydrogenation pathway, the potential limiting steps of the NRR reaction in different catalyst systems and their corresponding theoretical overpotentials were determined. The closer the theoretical overpotential is to 0V, the better the performance. Generally, the theoretical overpotential of non-noble metal catalysts often falls in the range of 0.5–0.7V, which is considered good. The theoretical overpotential of NRR between 0.3V and 0.5V is generally considered very promising. If the theoretical overpotential can be reduced to below 0.3V through catalyst design, it often indicates that the material may have excellent activity and selectivity, making it an ideal research target. Taking Ru-C6N3 and Pt-C6N3 as examples, their corresponding theoretical overpotentials of NRR are 0.39V and 0.37V, respectively.

[0080] In summary, as demonstrated by the specific embodiments described above, the ORR / NRR catalyst design method for C6N3 two-dimensional materials supported by transition metal single atoms proposed in this invention can sequentially complete catalyst configuration construction, single-atom anchoring screening, reactant adsorption behavior analysis, and catalytic performance evaluation based on reaction pathways within a unified design framework. It also enables systematic screening and performance determination of oxygen reduction reaction and electrocatalytic nitrogen reduction reaction, respectively. This method has a clear process and well-defined evaluation criteria, and is applicable to TM-C6N3 catalyst systems supported by different transition metal single atoms, providing an feasible technical solution for the rational design and screening of ORR and NRR catalysts.

[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for screening catalysts for C6N3 two-dimensional materials supported by a single atom of a transition metal, characterized in that the method... include: S1. Construct a periodic structural model of the two-dimensional material C6N3; S2. Transition metal atoms are introduced into the nitrogen-rich pore sites of the periodic structure model to form a TM-C6N3 catalyst model supported by transition metal atoms. S3. Optimize the structure of the TM-C6N3 catalyst model and calculate the binding energy between the transition metal atoms and the C6N3 substrate. Select stable configurations of the TM-C6N3 catalyst with binding energies less than 0. S4. Calculate the adsorption free energies of the target reactant molecules O2 and N2 at the transition metal sites on the surface of the stable configuration of the TM-C6N3 catalyst, and perform preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the adsorption free energies to obtain a set of candidate catalysts. S5. Evaluate the catalytic performance of the candidate catalyst set for oxygen reduction reaction and nitrogen reduction reaction to obtain a TM-C6N3 catalyst suitable for oxygen reduction reaction and electrocatalytic nitrogen reduction reaction.

2. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 1, characterized in that, In step S2, the transition metal single atom is selected from at least one of 3d, 4d, or 5d transition metal elements.

3. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 1, characterized in that, In step S4, the preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the adsorption free energy includes the following steps: The stable configuration of the TM-C6N3 catalyst with adsorption free energies of O2 and N2 both less than 0 eV was retained to obtain the candidate catalyst set.

4. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 1, characterized in that, The evaluation of the catalytic performance of the oxygen reduction reaction includes: A multi-electron reaction pathway model for the oxygen reduction reaction was constructed, and the free energy changes of each elementary reaction step in the oxygen reduction reaction pathway were calculated using a hydrogen electrode model. The step corresponding to the maximum value of the free energy change of the oxygen reduction reaction is regarded as the potential limiting step of the oxygen reduction reaction. Calculate the theoretical overpotential of the oxygen reduction reaction corresponding to the potential limiting step of the oxygen reduction reaction, and evaluate the catalytic activity of the oxygen reduction reaction based on the theoretical overpotential.

5. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 1, characterized in that, The evaluation of the catalytic performance of the electrocatalytic nitrogen reduction reaction includes: A stepwise protonation reaction pathway model was constructed, and the free energy changes of each reaction step were calculated. The step corresponding to the maximum value of the free energy change of the electrocatalytic nitrogen reduction reaction is regarded as the potential limiting step of the electrocatalytic nitrogen reduction reaction. Calculate the theoretical overpotential of the electrocatalytic nitrogen reduction reaction corresponding to the potential limiting step of the electrocatalytic nitrogen reduction reaction, and evaluate the catalytic activity of the electrocatalytic nitrogen reduction reaction based on the theoretical overpotential.

6. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 4, characterized in that, When the theoretical overpotential of the oxygen reduction reaction is less than 0.7 V, the catalyst is deemed to have good ORR activity.

7. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 5, characterized in that, When the theoretical overpotential of the electrocatalytic nitrogen reduction reaction is less than 0.5 V, the catalyst is deemed to have excellent NRR activity.

8. The catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to claim 5, characterized in that, The evaluation of the catalytic performance of the electrocatalytic nitrogen reduction reaction also includes: analyzing the relationship between the free energy of key free bodies and the descriptor during the electrocatalytic nitrogen reduction reaction, in order to help screen catalysts with better electrocatalytic nitrogen reduction catalytic potential.

9. A catalyst screening system for a transition metal single-atom supported C6N3 two-dimensional material, characterized in that, include: The module includes a model building module, a stability module, a preliminary screening module, and a performance evaluation module. The model building module is used to construct a periodic structure model of the two-dimensional material C6N3; transition metal atoms are introduced at the nitrogen-rich pore sites of the periodic structure model to form a TM-C6N3 catalyst model supported by transition metal atoms. The binding stabilization module is used to optimize the structure of the TM-C6N3 catalyst model, calculate the binding energy between transition metal atoms and the C6N3 substrate, and screen out stable configurations of the TM-C6N3 catalyst with binding energies all less than 0. The preliminary screening module is used to calculate the adsorption free energies of target reactant molecules O2 and N2 at the transition metal sites on the surface of the stable configuration of the TM-C6N3 catalyst, and to perform preliminary screening of the stable configuration of the TM-C6N3 catalyst based on the comparison between the adsorption free energies and the screening threshold, thereby obtaining a set of candidate catalysts. The performance evaluation module is used to evaluate the catalytic performance of the candidate catalyst set for oxygen reduction reaction and nitrogen reduction reaction, so as to obtain a TM-C6N3 catalyst suitable for oxygen reduction reaction and electrocatalytic nitrogen reduction reaction.

10. An electronic device, characterized in that, include: Memory, used to store computer programs; When the processor executes the computer program stored in the memory, it implements the steps of the catalyst screening method for a transition metal single-atom supported C6N3 two-dimensional material according to any one of claims 1-8.

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