A Screening Method for Carbon-Based Models Loaded with Rare Earth Oxide Clusters for Efficient Catalysis of Oxygen Electrode Reactions

Abstract

The present invention discloses a screening method for a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction, obtaining and optimizing the REO crystal model, determining the specific crystal form formed by the crystal with preferential growth crystal planes based on thermodynamics, establishing an m×n×k supercell, constructing a cluster model of the specific crystal form, further optimizing the model to determine the most stable minimum REO cluster configuration, screening the stable catalyst configuration through the formation energy of the bond between the cluster and the carbon substrate, dividing the efficient ORR and OER catalyst candidate regions through the screening mechanism, and applying the catalyst only existing in the efficient ORR catalyst candidate region to the positive electrode catalysis of a primary fuel cell / metal-air battery; the catalyst only existing in the efficient OER catalyst candidate region is used in the field of oxygen evolution reaction; the catalyst existing in both the efficient ORR and OER candidate regions is applied to the oxygen electrode catalysis of a secondary fuel cell / metal-air battery. Explore the ORR and OER paths, reveal the catalytic mechanism, and provide guidance for the design and development of oxygen electrode catalysts.

Description

Technical Field

[0001] The present invention relates to the technical fields of high-performance rare earth functional materials and their application technologies, and new catalyst screening technologies, and particularly relates to a screening method for a carbon-based model loaded with rare earth oxide clusters for efficiently catalyzing oxygen electrode reactions. Background Art

[0002] New energy devices based on electrochemical energy storage and conversion technologies, such as reversible fuel cells and zinc-air batteries, are beneficial to reducing human dependence on traditional fossil fuels and reducing carbon emissions. However, the reaction efficiency of the oxygen electrode involved in this technology is low, which hinders the commercial promotion and application of the technology. Traditionally, noble metal platinum is used as the oxygen reduction reaction (ORR) catalyst, and oxides of noble metals ruthenium (Ru) and iridium (Ir) are used as the catalysts for the oxygen evolution reaction. Although these several traditional noble metal catalysts have good catalytic activity, due to disadvantages such as low abundance, high cost, poor durability, and the single-function of the oxygen-involved reaction catalysis, the further development of this technology is restricted. Therefore, the development of efficient, inexpensive, and stable oxygen electrode reaction catalysts is of great significance for the development of electrochemical energy storage and conversion technologies and the solution of global energy crisis and environmental pollution problems.

[0003] Investigations have found that the global rare earth reserves in 2019 were 120 million tons. In terms of abundance in the earth's crust, the highest, cerium, is close to copper, and the lowest, lutetium, is more than 200 times higher than gold. Rare earth elements have a unique multi-electron structure and excellent magnetic, optical, and electrical properties, and are widely used in many important fields of scientific research and industrial manufacturing, including metallurgy, electronics, and catalysis. Shrinking rare earth metals to the atomic scale is an effective strategy to improve the metal utilization efficiency. In addition, the unique structural characteristics of rare earth metals at the atomic scale will endow them with unexpected properties.

[0004] There are countless catalyst synthesis techniques. It is not difficult to synthesize a catalyst with a specific structure. The difficulty lies in the confusion about what kind of structure to synthesize. To find the best catalyst, traditional experimental synthesis uses an inefficient trial-and-error method. According to literature, experience, etc., the reactant reference is adjusted to design multiple experimental schemes. Through processes such as the solvent method, chemical deposition method, and high-temperature calcination method, catalysts with different components and structures are synthesized. The material structure, microscopic morphology size, pore size, and other phase information of the synthesized precursor and Tm–N–C@SACs samples are characterized by modern testing and analysis means (such as X-ray diffraction XRD, high-resolution transmission electron microscopy HRTEM, scanning electron microscopy SEM, etc.); energy dispersive spectrometer EDS, inductively coupled plasma mass spectrometry ICP–MS, and X-ray-derived spectra such as X-ray photoelectron spectroscopy XPS, X-ray absorption near-edge spectroscopy XANES, and extended X-ray absorption fine structure EXAFS are used to characterize the elemental composition and distribution, chemical valence state, coordination relationship, and other composition and configuration information of the samples. The in-situ measurement of ultraviolet-visible spectroscopy combined with electrochemistry is carried out using a three-electrode system. Specifically, it includes catalyst poisoning experiments, cyclic voltammetry CV scans and linear sweep voltammetry LSV scans, electrochemical impedance spectroscopy EIS tests, cyclic durability tests, and potentiostatic durability tests, etc. By optimizing the process, directional synthesis and optimization of catalytic performance are achieved, and the best process preparation conditions are determined.

[0005] Traditional techniques not only make it difficult to cover all potential catalysts, but also have disadvantages such as high resource consumption, long experimental cycle, large "three wastes" emissions, unpredictable product performance, high trial-and-error costs, and poor repeatability.

[0006] The existing technology also has the following disadvantages:

[0007] 1) It is difficult for the existing technology to cover all catalyst configurations in the studied system, which is likely to cause the omission of potential high-performance catalysts.

[0008] 2) The existing technology first synthesizes products through experiments, and then conducts product characterization and electrochemical performance tests. Due to the unknown catalytic mechanism, catalysts with poor performance cannot be filtered in advance, resulting in a large waste of resources such as time, manpower, and material resources.

[0009] 3) The existing technology involves experimental synthesis and electrical performance testing, plus subsequent process optimization, with huge consumption of materials, and at the same time accompanied by a large amount of "three wastes" emissions, which is extremely unfriendly to the environment.

[0010] 4) The experimental synthesis process has many steps, large environmental variables, and strong human interference, often resulting in the non-repeatability of experiments.

[0011] 5) The cost of experimental research is high, including three major parts: catalyst preparation, catalyst characterization, and catalytic performance testing. Especially for catalyst characterization, the products need to be sent out for testing, which is time-consuming, laborious, and costly.

[0012] For the existing technology, what is lacking currently is not the catalyst synthesis technology, but the effective design and guidance for the directional synthesis of catalysts with specific functions.

[0013] Based on the theoretical research of the first-principles, the present invention has the characteristics of complete configuration coverage, less resource consumption, short research cycle, no "three wastes" emission, clear catalytic mechanism, high repeatability, etc., and will provide precise guidance for experimental synthesis. For this reason, the present invention combines the excellent characteristics of rare earths and develops a screening method for rare earth oxide cluster-loaded carbon-based models that can efficiently catalyze the oxygen electrode reaction based on the first-principles. Summary of the Invention

[0014] The purpose of the present invention is to overcome the shortcomings of the existing technology and disclose a screening method for rare earth oxide cluster-loaded carbon-based models that can efficiently catalyze the oxygen electrode reaction. Obtain the REO crystal structure model and optimize it to obtain the optimal structure. Based on thermodynamics, judge the specific crystal form formed by the crystal with the preferentially growing crystal plane self-limiting. Establish an m×n×k supercell, construct the cluster configuration of the specific crystal form, further optimize the model to determine the most stable and smallest REO cluster configuration. Screen the stable catalyst configurations through the formation energy of the bond between the cluster and the carbon substrate. Divide the catalyst candidate areas through the ORR and OER screening mechanisms respectively. The catalysts that only exist in the efficient ORR catalyst candidate area can be applied to the positive electrode catalysis of primary fuel cells / metal-air batteries; the catalysts that only exist in the efficient OER catalyst candidate area can be used in the field of oxygen production; the catalysts that exist in both the efficient ORR and OER candidate areas can be applied to the oxygen electrode catalysis of secondary fuel cells / metal-air batteries. Explore the paths of ORR and OER respectively, overcome the deficiencies of the existing technology in unclear catalytic mechanisms, carry out theoretical research based on the first-principles, provide a screening method for predicting rare earth oxide cluster-loaded carbon-based models that can efficiently catalyze the oxygen electrode reaction, reveal the catalytic mechanism, and provide guidance for experimental synthesis.

[0015] To achieve the above object, the technical solution adopted in the present application is as follows:

[0016] A screening method for rare earth oxide cluster-loaded carbon-based models that can efficiently catalyze the oxygen electrode reaction, comprising the following steps:

[0017] Step S1: Obtain the REO crystal model through different channels and optimize it to obtain the optimal structure. Based on thermodynamics, judge the growth priority of different crystal planes, obtain the growth rules of different crystal planes and the specific crystal form formed by the final crystal with the preferentially growing crystal plane self-limiting. Establish an m×n×k supercell, determine the cluster configuration of the specific crystal form composed of the target components according to the preferentially growing crystal plane, remove the redundant atoms to construct a cluster model with the smallest size, and further optimize the model to determine the most stable and smallest REO cluster configuration;

[0018] Step S2: Load the cluster configurations obtained in Step S1 onto the carbon-based material through point, line, and surface contacts, and calculate the formation energy ΔE of the bond formation between the cluster and the carbon substrate. b , and screen for stable catalyst configurations based on ΔE b ; screen for stable catalyst configurations with ΔE < 0 eV, and determine the optimal configurations of point, line, surface, etc. loading patterns according to the principle of the lowest energy.

[0019] Step S3: Screen for efficient ORR catalysts according to the ORR screening mechanism and classify them into the ORR catalyst candidate area; the specific method is as follows:

[0020] Step S31: Construct an O2 adsorption model for different active centers of the catalyst, select the adsorption model with the lowest energy, and calculate the adsorption energy of the catalyst for O2. According to screen for catalyst models with sufficient O2 adsorption.

[0021] Step S32: Construct an adsorption model of the catalyst for H2O and optimize the structure, and calculate the adsorption energy of the catalyst for H2O. To avoid catalyst passivation by the solvent and ensure the recyclability of the catalyst, according to screen for catalysts with weak or no H2O adsorption.

[0022] Step S33: Construct an OH adsorption model and optimize the configuration, and calculate the OH adsorption energy ΔE *OH , and use ΔE *OH > -3.5 eV as the boundary to preliminarily screen for catalysts with appropriate OH adsorption; if ΔE *OH < -3.5 eV, it indicates that OH is difficult to desorb. Take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening, and continue to explore the catalytic performance of other active sites in the case of OH coordination.

[0023] Step S34: Consider the influence of zero-point vibrational energy and entropy on the Gibbs free energy, perform further calculations on the OH adsorption model, and obtain a more accurate OH adsorption free energy ΔG *OH , and according to ΔG *OH > 0.4 eV, more accurately screen for catalysts with appropriate OH adsorption; for the OH adsorption model with ΔG *OH < 0.4 eV, take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening, and continue to explore the catalytic performance of other active sites in the case of OH coordination.

[0024] Step S35: Discard catalysts with too weak or no OH adsorption according to ΔG *OH > 1.6 eV.

[0025] Step S36: Calculate the reaction energy ΔG for the side reaction of the adsorbed OOH and free H2O to generate HOOH respectively.*OOH→HOOH and the main reaction generates adsorbed O and free OH – reaction energy ΔG2 of ORR . According to ΔG *OOH→HOOH >ΔG2 ORR , screen the catalyst that is more favorable for the energy of the main reaction;

[0026] Step S37: Determine the reaction energy of the 4-step electron transfer process and calculate the ORR overpotential η ORR magnitude, and classify η ORR <0.8V into the candidate area of high-efficiency ORR catalysts; the 4-step electron transfer processes are respectively: O2+*+H2O+e – → * OOH+OH – ; * OOH+e – → * O+OH – ; * O+H2O+e – → * OH+OH – ; * OH+e – →*+OH – ;

[0027] Step S4: Screen high-efficiency OER catalysts according to the oxygen evolution reaction OER screening mechanism; the specific method is:

[0028] Step S41: Calculate the OH adsorption energy ΔE *OH , and screen the model with sufficient OH adsorption according to ΔE *OH <–1eV;

[0029] Step S42: Calculate the adsorption energy of the catalyst for H2O According to screen the catalyst with appropriate OH and H2O adsorption;

[0030] Step S43: Calculate the adsorption energy of the catalyst for O2 According to screen the catalyst model with weak O2 adsorption;

[0031] Step S44: Consider the influence of zero-point vibrational energy and entropy on the Gibbs free energy, and perform further calculations on the OH adsorption model to obtain a more accurate OH adsorption free energy ΔG *OH , and screen the catalyst with appropriate OH adsorption more accurately according to ΔG *OH >0.4eV; for ΔG *OHThe OH adsorption model with <0.4 eV takes OH as a ligand and incorporates it into the OER screening mechanism for re-screening, and continues to explore the catalytic performance of other active sites under OH coordination;

[0032] Step S45: According to ΔG *OH > 1.6 eV, catalysts with too weak OH adsorption are excluded;

[0033] Step S46: Calculate the reaction energy ΔG of the side reaction to generate HOOH from the adsorbed OH and free OH – respectively, *OH→HOOH as well as the reaction energy ΔG2 of the main reaction to generate adsorbed O and free H2O; According to ΔG OER ; *OH→HOOH > ΔG2 OER , catalysts that are more favorable for the main reaction energy are screened;

[0034] Step S47: Determine the reaction free energy of the 4-step electron transfer process, and calculate the OER overpotential η OER magnitude, and classify the catalyst with η OER < 0.8 V into the candidate area of high-efficiency OER catalysts; The 4-step electron transfer process is: OH – + * → *OH + e – ; *OH + OH – → *O + H2O + e – ; *O + OH – → *OOH + e – ; *OOH + OH – → O2 + * + H2O + e – .

[0035] Step S5: Aggregate the catalysts obtained from the ORR and OER screening mechanisms. Catalysts that only exist in the candidate area of high-efficiency ORR catalysts can be applied to the positive electrode catalysis of primary fuel cells / metal-air batteries; Catalysts that only exist in the candidate area of high-efficiency OER catalysts can be used in the oxygen evolution reaction domain; For catalysts that exist in both the high-efficiency ORR and OER candidate areas, they can be applied to the oxygen electrode catalysis of secondary fuel cells / metal-air batteries. Explore the reaction path, reveal the catalytic mechanism, and provide guidance for the design and development of reversible battery oxygen electrode catalysts and experimental synthesis.

[0036] Furthermore, the REO crystal structure models obtained through different channels in step S1 are crystal structure websites and literature channels.

[0037] Furthermore, in step S2, the cluster configurations are loaded on the carbon-based material in the form of point, line, and surface contacts. The point form is O–C and RE–C, the line form is Line–C, and the surface form is Face–C; In step S2, calculate the formation energy ΔE of the bond formation between the cluster and the carbon substrateb The specific method is as follows:

[0038] ΔE b = E * – E C – E REO

[0039] Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, E C and E REO refer to the energies of the carbon-based and REO cluster molecules respectively.

[0040] Furthermore, the specific method for calculating the adsorption energy of O2 by the catalyst in step S31 and step S43 is as follows:

[0041]

[0042] Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, refers to the total energy of the system where the catalyst adsorbs O2, refers to the energy of a single O2 molecule;

[0043] The specific method for calculating the adsorption energy of H2O by the catalyst in step S32 and step S42 is as follows:

[0044]

[0045] Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, refers to the energy of the system where the catalyst adsorbs H2O, refers to the energy of the H2O molecule.

[0046] Furthermore, the specific method for calculating the OH adsorption energy ΔE *OH is as follows:

[0047] ΔE *OH = E *OH – E * – E OH

[0048] Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, E *OH refers to the energy of the system where the catalyst adsorbs OH, E OH refers to the energy of OH.

[0049] Furthermore, the specific method for calculating the OH adsorption free energy ΔG in step S34 and step S44*OH The specific method is as follows:

[0050]

[0051] Among them, G * and G *OH respectively refer to the Gibbs free energy of the REO cluster-loaded carbon-based catalyst and the system where the catalyst adsorbs OH, and respectively refer to the Gibbs free energy of a single H2O and H2 molecule.

[0052] Furthermore, the specific method for calculating the reaction energy ΔG *OOH→HOOH of the side reaction of adsorbed OOH and free H2O to generate HOOH and the main reaction to generate adsorbed O and free OH – with the reaction energy ΔG2 ORR is as follows:

[0053]

[0054]

[0055] Among them, G * refers to the Gibbs free energy of the REO cluster-loaded carbon-based catalyst, G *OOH and G *O respectively refer to the Gibbs free energy of the catalyst adsorbing OOH and the single-atom O system, G HOOH , and respectively refer to the Gibbs free energy of a single HOOH, H2O, and H2 molecule, and pH is the hydrogen ion concentration index of the catalytic environment.

[0056] Furthermore, the specific method for determining the reaction energy of the 4-step electron transfer process in step S37 is as follows:

[0057]

[0058]

[0059]

[0060]

[0061] Among them, ΔG1 ORR is the reaction energy of O2+*+H2O+e – → * OOH+OH – and ΔG2 ORR is * OOH+e – → *O + OH – Reaction energy of, ΔG3 ORR is * O + H2O + e – → * OH + OH – Reaction energy of, ΔG4 ORR is * OH + e – → * + OH – Reaction energy of, G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, G *OOH , G *O and G *OH respectively refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems, and respectively refer to the Gibbs free energies of H2O, H2, and O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment;

[0062] The specific method for calculating the ORR overpotential η ORR is as follows:

[0063] η ORR = 0.402 + max(ΔG1 ORR , ΔG2 ORR , ΔG3 ORR , ΔG4 ORR ) / e

[0064] where, ΔG1 ORR is the reaction energy of O2 + * + H2O + e – → * OOH + OH – Reaction energy of, ΔG2 ORR is for free * OOH + e – → * O + OH – Reaction energy of, ΔG3 ORR is * O + H2O + e – → * OH + OH – Reaction energy of, ΔG4 ORR is * OH + e – → * + OH – Reaction energy of, e is the elementary charge.

[0065] Furthermore, in step S46, the reaction energy ΔG of the side reaction that generates HOOH by calculating adsorbed OH and free OH – respectively *OH→HOOHand the reaction energy ΔG2 for the main reaction to generate adsorbed O and free H2O OER The specific method is as follows:

[0066]

[0067]

[0068] where G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, and G *OOH , G *O and G *OH refer to the Gibbs free energies of the catalyst adsorbed OOH, single-atom O, and OH systems respectively. G HOOH , and refer to the Gibbs free energies of single HOOH, H2O, and H2 molecules respectively, and pH is the hydrogen ion concentration index of the catalytic environment.

[0069] Furthermore, the specific method for determining the reaction energies of the 4-step electron transfer process in step S47 is as follows:

[0070]

[0071]

[0072]

[0073]

[0074] where ΔG1 OER is the reaction energy of OH – +*→*OH+e – ΔG2 OER is the reaction energy of *OH+OH – →*O+H2O+e – ΔG3 OER is the reaction energy of *O+OH – →*OOH+e – ΔG4 OER is the reaction energy of *OOH+OH – →O2+*+H2O+e – G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, and G *OOH , G *O and G *OH refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems respectively, and They respectively refer to the Gibbs free energies of H2O, H2, and O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment;

[0075] The specific method for calculating the OER overpotential η OER is as follows:

[0076] η OER = max(ΔG1 OER , ΔG2 OER , ΔG3 OER , ΔG4 OER ) / e–0.402

[0077] where ΔG1 OER is the reaction energy of OH – + * → *OH + e – , ΔG2 OER is the reaction energy of *OH + OH – → *O + H2O + e – , ΔG3 OER is the reaction energy of *O + OH – → *OOH + e – , ΔG4 OER is the reaction energy of *OOH + OH – → O2 + * + H2O + e – , and e is the elementary charge.

[0078] The beneficial effects of the present invention are as follows:

[0079] The present invention proposes a screening method for a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction. Compared with existing methods, the advantages are as follows:

[0080] 1. The invention conducts theoretical research on catalysts based on a high-performance server, and the research content covers all potential configurations, which is different from the narrow trial and error of experiments and effectively avoids the omission of potentially efficient catalysts.

[0081] 2. The invention adopts a rigorous progressive screening process, which is different from the blind trial and error of pure experiments, and is conducive to accurately and quickly locating potential high-performance catalyst configurations, with less resource consumption and a short research cycle, etc.

[0082] 3. The invention conducts research based on a computer, which is different from the large resource consumption and "three wastes" emissions of experimental synthesis. The invention only consumes part of the electricity and has no pollution emissions, which is conducive to energy conservation and environmental protection.

[0083] 4. The invention conducts computational research based on first principles, which is different from the disadvantages of strong interference and poor repeatability caused by environmental and human factors in experiments, and has the characteristics of high accuracy and high repeatability.

[0084] 5. The invention reveals the catalytic path and mechanism at the atomic scale, compensating for the shortcoming of unclear catalytic mechanism in experiments, and is conducive to guiding experimental synthesis and further popularization and application.

[0085] 6. The invention can be extended to the design and research and development of different crystal form cluster-supported catalysts, not limited to rare earth oxides, fixed crystal forms, and fixed catalytic functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Figure 1 It is a flow chart of a screening method for a rare earth oxide cluster-supported carbon-based model for efficiently catalyzing the oxygen electrode reaction in an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0087] The present invention will be further described below in conjunction with the drawings. The protection scope of the present invention is not limited to the following:

[0088] Example 1:

[0089] As Figure 1 shown, according to the flow chart of the screening method for a rare earth oxide cluster-supported carbon-based model for efficiently catalyzing the oxygen electrode reaction;

[0090] Taking La2O3 cluster-supported graphene as an example, the specific implementation method is as follows.

[0091] 1) Optimize the La2O3 crystal model to obtain the optimal structure, establish a 2×2×1 supercell, remove redundant atoms to construct a La2O3 cluster model with the smallest size, and further optimize the model to determine the most stable minimum La2O3 cluster configuration.

[0092] 2) Load the obtained La2O3 clusters on graphene in the forms of points (O–C and RE–C), lines (Line–C), planes (Face–C), etc., and calculate the formation energy ΔE b of the bond formation between the clusters and graphene. According to ΔE b <0 eV, screen the stable catalyst configurations. And determine the optimal configurations of the point, line, plane, etc. loading forms according to the principle of the lowest energy.

[0093] The specific method for calculating the formation energy ΔE b of the bond formation between the La2O3 cluster and graphene is as follows:

[0094] ΔE b = E * – E C– E REO

[0095] where E * refers to the total energy of the La2O3 cluster-supported graphene system, E C and EREO Refer to the energies of graphene and La2O3 cluster molecules respectively.

[0096] 3) Discuss the reaction mechanisms of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) separately.

[0097] ORR screening mechanism:

[0098] a) Construct O2 adsorption models (side–on, end–on, bridge–on) for different active centers of the catalyst, select the adsorption model with the lowest energy, and calculate the adsorption energy of the catalyst for O2 According to Screen the catalyst models with sufficient O2 adsorption.

[0099] The specific method for calculating the adsorption energy of the catalyst for O2 is as follows:

[0100]

[0101] where E * refers to the energy of the La2O3 cluster-loaded graphene catalyst, refers to the total energy of the system where the catalyst adsorbs O2, refers to the energy of a single O2 molecule;

[0102] b) Construct an adsorption model of the catalyst for H2O and optimize the structure, and calculate the adsorption energy of the catalyst for H2O According to Screen the catalysts with weak or no H2O adsorption.

[0103] The specific method for calculating the adsorption energy of the catalyst for H2O is as follows:

[0104]

[0105] where E * refers to the energy of the La2O3 cluster-loaded graphene catalyst, refers to the energy of the system where the catalyst adsorbs H2O, refers to the energy of the H2O molecule.

[0106] c) Construct an OH adsorption model and optimize the configuration, calculate the OH adsorption energy ΔE *OH , and screen the catalysts with appropriate OH adsorption with ΔE *OH > –3.5 eV. If ΔE *OH < –3.5 eV, take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening.

[0107] The specific method for calculating the OH adsorption energy ΔE *OHThe specific method is as follows:

[0108] ΔE *OH = E *OH – E * – E OH

[0109] Wherein, E * refers to the energy of the La2O3 cluster-loaded graphene catalyst, and E *OH refers to the energy of the system in which the catalyst adsorbs OH, and E OH refers to the energy of OH.

[0110] d) Obtain the free energy of OH adsorption ΔG *OH , and according to ΔG *OH > 0.4 eV, screen the catalysts with appropriate OH adsorption. For the OH adsorption model with ΔG *OH < 0.4 eV, take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening.

[0111] The specific method for calculating the free energy of OH adsorption ΔG *OH is as follows:

[0112]

[0113] Wherein, G * and G *OH respectively refer to the Gibbs free energy of the La2O3 cluster-loaded graphene catalyst and the system in which the catalyst adsorbs OH, and respectively refer to the Gibbs free energy of a single H2O and H2 molecule.

[0114] e) Discard the catalysts with too weak OH adsorption or even no adsorption according to ΔG *OH > 1.6 eV.

[0115] f) Calculate ΔG *OOH→HOOH and ΔG2 ORR respectively. According to ΔG *OOH→HOOH > ΔG2 ORR , screen the catalysts that are favorable for the main reaction energy.

[0116] The specific method for calculating the reaction energy ΔG *OOH→HOOH of the side reaction of the adsorbed OOH and free H2O to generate HOOH and the reaction energy ΔG2 – of the main reaction to generate adsorbed O and free OH ORR is as follows:

[0117]

[0118]

[0119] Among them, G * refers to the Gibbs free energy of the La2O3 cluster-loaded graphene catalyst, G *OOH and G *O respectively refer to the Gibbs free energies of the catalyst adsorbed OOH and single-atom O systems, G HOOH 、 and respectively refer to the Gibbs free energies of single HOOH, H2O, and H2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment.

[0120] g) Determine the reaction energy of the 4-step electron transfer process and calculate the ORR overpotential η ORR magnitude, and classify η ORR < 0.8 V into the candidate region for highly efficient ORR catalysts.

[0121] The specific method for determining the reaction energy of the 4-step electron transfer process is as follows:

[0122]

[0123]

[0124]

[0125]

[0126] Among them, ΔG1 ORR is the reaction energy of O2 + * + H2O + e – → * OOH + OH – ΔG2 ORR is * OOH + e – → * O + OH – ΔG3 ORR is * O + H2O + e – → * OH + OH – ΔG4 ORR is * OH + e – → * + OH – G * refers to the Gibbs free energy of the La2O3 cluster-loaded graphene catalyst, G *OOH 、G *O and G *OH respectively refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems, and They respectively refer to the Gibbs free energies of H2O, H2, and O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment;

[0127] The specific method for calculating the ORR overpotential η ORR is as follows:

[0128] η ORR = 0.402 + max(ΔG1 ORR , ΔG2 ORR , ΔG3 ORR , ΔG4 ORR ) / e

[0129] where ΔG1 ORR is the reaction energy of O2 + * + H2O + e – → * OOH + OH – ΔG2 ORR is the reaction energy of free * OOH + e – → * O + OH – ΔG3 ORR is * the reaction energy of O + H2O + e – → * OH + OH – ΔG4 ORR is * the reaction energy of OH + e – → * + OH – e is the elementary charge.

[0130] OER screening mechanism:

[0131] a) Screen the model with sufficient OH adsorption according to ΔE *OH < –1 eV.

[0132] b) Screen the catalyst with appropriate OH and H2O adsorption according to ΔE *OH < ΔE *H2O .

[0133] c) Screen the catalyst model with weak O2 adsorption according to .

[0134] d) Screen the catalyst with appropriate OH adsorption according to ΔG *OH > 0.4 eV. If ΔG *OH < 0.4 eV, then consider OH as a ligand modification.

[0135] e) Eliminate the catalyst with too weak OH adsorption according to ΔG *OH > 1.6 eV.

[0136] f) Calculate ΔG and ΔG2 separately. *OH→HOOH and ΔG2 OER . According to ΔG *OH→HOOH > ΔG2 OER , screen the catalysts that are favorable for the energy of the main reaction.

[0137] The specific method for separately calculating the reaction energies of adsorbed OH and free OH – for the side reaction to generate HOOH, ΔG *OH→HOOH and the reaction energy of the main reaction to generate adsorbed O and free H2O, ΔG2 OER is as follows:

[0138]

[0139]

[0140] where G * refers to the Gibbs free energy of the La2O3 cluster-loaded graphene catalyst, and G *OOH , G *O and G *OH refer to the Gibbs free energies of the catalyst adsorbed OOH, single-atom O, and OH systems respectively, and G HOOH , and refer to the Gibbs free energies of a single HOOH, H2O, and H2 molecule respectively, and pH is the hydrogen ion concentration index of the catalytic environment.

[0141] g) Determine the reaction free energy of the 4-step electron transfer process and calculate the OER overpotential η OER value. Catalysts with η OER < 0.8 V are included in the candidate area for efficient OER catalysts.

[0142] The specific method for determining the reaction energy of the 4-step electron transfer process is as follows:

[0143]

[0144]

[0145]

[0146]

[0147] where ΔG1 OER is the reaction energy of OH – + * → *OH + e – , ΔG2 OER is the reaction energy of *OH + OH – → *O + H2O + e – , and ΔG3 OERFor *O + OH – → *OOH + e – The reaction energy, ΔG4 OER For *OOH + OH – → O2 + * + H2O + e – The reaction energy, G * Refers to the Gibbs free energy, G, of the La2O3 cluster-loaded graphene catalyst *OOH G *O And G *OH Respectively refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems And Respectively refer to the Gibbs free energies of H2O, H2, and O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment

[0148] The specific method for calculating the OER overpotential η OER Is as follows:

[0149] η OER = max(ΔG1 OER , ΔG2 OER , ΔG3 OER , ΔG4 OER ) / e – 0.402

[0150] Among them, ΔG1 OER Is the reaction energy of OH – + * → *OH + e – The reaction energy, ΔG2 OER Is for *OH + OH – → *O + H2O + e – The reaction energy, ΔG3 OER Is for *O + OH – → *OOH + e – The reaction energy, ΔG4 OER Is for *OOH + OH – → O2 + * + H2O + e – The reaction energy, and e is the elementary charge

[0151] 4) Summarize the La2O3-loaded graphene catalysts obtained by the ORR and OER screening mechanisms, screen out the highly efficient bifunctional catalysts that simultaneously exist in the high-efficiency ORR and OER candidate regions, clarify the ORR and OER paths, reveal the catalytic mechanism, and provide guidance for experimental synthesis and further research

[0152] In summary, the present invention discloses a screening method for a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction, obtaining and optimizing the REO crystal model, determining the specific crystal form formed by the crystal self-limiting growth on the preferential growth crystal plane based on thermodynamics, establishing an m×n×k supercell, constructing the cluster configuration of the specific crystal form, further optimizing the model to determine the most stable minimum REO cluster configuration, screening the stable catalyst configuration through the formation energy of the bond between the cluster and the carbon substrate, dividing the catalyst candidate areas through the ORR and OER screening mechanisms respectively, and the catalyst that only exists in the efficient ORR catalyst candidate area can be applied to the positive electrode catalysis of primary fuel cells / metal-air batteries; the catalyst that only exists in the efficient OER catalyst candidate area can be used in the field of oxygen production; the catalyst that exists in both the efficient ORR and OER candidate areas can be applied to the oxygen electrode catalysis of secondary fuel cells / metal-air batteries. The paths of ORR and OER are respectively explored, and the catalytic mechanism is revealed to provide guidance for experimental synthesis.

[0153] At this point, those skilled in the art will recognize that although the embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived from the content disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and determined to cover all these other variations or modifications.

Claims

1. A screening method for a carbon-based model loaded with rare earth oxide clusters for efficiently catalyzing the oxygen electrode reaction, characterized in that, The screening method includes the following steps: Step S1: Obtain the REO crystal model through different channels and optimize it to obtain the optimal structure. Based on thermodynamics, judge the growth priority of different crystal planes, obtain the growth rules of different crystal planes, and the final crystal self-limits to form a specific crystal form with the preferentially growing crystal plane. Establish an m×n×k supercell, determine the cluster configuration with a specific crystal form composed of the target components according to the preferentially growing crystal plane, remove the redundant atoms to construct the smallest-size cluster model, and further optimize the model to determine the most stable smallest REO cluster configuration; Step S2: Load the cluster configurations obtained in Step S1 onto the carbon-based material through point, line, and surface contacts, and calculate the formation energy ΔE of the bond formed between the cluster and the carbon substrate. b , and based on ΔE b filter out stable catalyst configurations with < 0 eV; and determine the optimal configurations for point, line, and surface loading types respectively according to the principle of the lowest energy. Step S3: Screen high-efficiency ORR catalysts according to the oxygen reduction reaction (ORR) screening mechanism and classify them into the ORR catalyst candidate area; the specific method is: Step S31: Construct an O2 adsorption model for different active centers of the catalyst, select the adsorption model with the lowest energy, and calculate the adsorption energy ΔE of the catalyst for O2 *O2 , according to ΔE *O2 < –0.5 eV, screen the catalyst models with sufficient O2 adsorption; Step S32: Construct an adsorption model of the catalyst for H2O and optimize the structure, and calculate the adsorption energy ΔE of the catalyst for H2O *H2O ; To avoid passivation of the catalyst by the solvent and ensure the recyclability of the catalyst, according to ΔE *O2 <ΔE *H2O Screen catalysts with weak or no H2O adsorption; Step S33: Construct an OH adsorption model and optimize the configuration, and calculate the OH adsorption energy ΔE *OH , taking ΔE *OH > –3.5 eV as the boundary to preliminarily screen the catalysts with appropriate OH adsorption; if ΔE *OH < –3.5 eV, it indicates that OH is difficult to desorb. Take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening, and continue to explore the catalytic performance of other active sites under the condition of OH coordination; Step S34: Considering the influence of zero-point vibrational energy and entropy on the Gibbs free energy, perform further calculations on the OH adsorption model to obtain a more accurate OH adsorption free energy ΔG *OH , according to ΔG *OH > 0.4 eV, more accurately screen the catalysts suitable for OH adsorption; for the OH adsorption model with ΔG *OH < 0.4 eV, take OH as a ligand and incorporate it into the ORR screening mechanism for re-screening, and continue to explore the catalytic performance of other active sites under OH coordination; Step S35: According to ΔG *OH > 1.6 eV, discard the catalysts with too weak OH adsorption or even no adsorption; Step S36: Calculate the reaction energy ΔG for the side reaction of the adsorbed OOH reacting with free H2O to form HOOH *OOH→HOOH and the reaction energy ΔG2 for the main reaction to form adsorbed O and free OH – ; According to ΔG ORR > ΔG2 *OOH→HOOH >, screen the catalyst that is more energetically favorable for the main reaction; ORR ​ Step S37: Determine the reaction energy of the four-step electron transfer process and calculate the ORR overpotential η ORR magnitude, and classify η ORR < 0.8V into the candidate region for highly efficient ORR catalysts; the four-step electron transfer processes are respectively: O2 + * + H2O + e – → * OOH + OH – ; * OOH + e – → * O + OH – ; * O + H2O + e – → * OH + OH – ; * OH + e – → * + OH – ; wherein, the * is the active site of the catalyst; Step S4: Screen high-efficiency OER catalysts according to the oxygen evolution reaction (OER) screening mechanism and classify them into the OER catalyst candidate area; the specific method is: Step S41: Calculate the OH adsorption energy ΔE *OH , and based on ΔE *OH < – 1 eV, screen the models with sufficient OH adsorption; Step S42: Calculate the adsorption energy ΔE of the catalyst for H2O *H2O , according to ΔE *OH <ΔE *H2O Screen the catalysts with appropriate OH and H2O adsorption; Step S43: Calculate the adsorption energy ΔE of the catalyst for O2 *O2 , and based on ΔE *O2 > –1 V, screen the catalyst models with weak O2 adsorption; Step S44: Considering the influence of zero-point vibrational energy and entropy on Gibbs free energy, perform further calculations on the OH adsorption model to obtain a more accurate OH adsorption free energy ΔG *OH , according to ΔG *OH > 0.4 eV, more precisely screen the catalysts suitable for OH adsorption; for the OH adsorption model with ΔG *OH < 0.4 eV, take OH as a ligand and incorporate it into the OER screening mechanism for re-screening, and continue to explore the catalytic performance of other active sites under OH coordination; Step S45: According to ΔG *OH > 1.6 eV, catalysts with too weak OH adsorption are excluded; Step S46: Calculate the adsorbed OH and free OH respectively – The reaction energy ΔG of the side reaction to generate HOOH *OH→HOOH and the reaction energy ΔG2 of the main reaction to generate adsorbed O and free H2O OER ; According to ΔG *OH→HOOH > ΔG2 OER , screen the catalyst that is more favorable for the energy of the main reaction; Step S47: Determine the reaction free energy of the four-step electron transfer process and calculate the OER overpotential η OER magnitude, and classify the catalyst with η OER < 0.8 V into the candidate region of high-efficiency OER catalysts; the four-step electron transfer process is as follows: OH – + * → *OH + e – ; *OH + OH – → *O + H2O + e – ; *O + OH – → *OOH + e – ; *OOH + OH – → O2 + * + H2O + e – ; wherein, the * is the active site of the catalyst; Step S5: Summarize the catalysts obtained by the ORR and OER screening mechanisms. The catalysts that only exist in the high-efficiency ORR catalyst candidate area are applied to the positive electrode catalysis of a primary fuel cell / metal-air battery; the catalysts that only exist in the high-efficiency OER catalyst candidate area are used in the field of oxygen evolution reaction; for the catalysts that exist in both the high-efficiency ORR and OER candidate areas, they are applied to the oxygen electrode catalysis of a secondary fuel cell / metal-air battery; In the step S36, calculate the reaction energy ΔG of the side reaction where the adsorbed OOH reacts with free H2O to generate HOOH *OOH→HOOH and the main reaction to generate adsorbed O and free OH – of the reaction energy ΔG2 ORR The specific method is as follows: ΔG *OOH→HOOH = G HOOH + G * + [G H2O – (0.5G H2 – 0.0592 × pH)] – G *OOH – G H2O ΔG2 ORR = G *O + G H2O – (0.5G H2 – 0.0592 × pH) – G *OOH Among them, G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, G *OOH and G *O respectively refer to the Gibbs free energies of the catalyst adsorbed OOH and single-atom O systems, G HOOH 、G H2O and G H2 respectively refer to the Gibbs free energies of single HOOH, H2O and H2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment; The specific method for determining the reaction energy of the 4-step electron transfer process in Step S37 is: ΔG1 ORR = G *OOH + G H2O –(0.5G H2 – 0.0592 × pH) – (G O2 + G * + G H2O ) ΔG2 ORR = G *O + G H2O –(0.5G H2 – 0.0592 × pH) – G *OOH ΔG3 ORR = G *OH + G H2O – (0.5G H2 – 0.0592 × pH) – (G *O + G H2O ) ΔG4 ORR = G * + G H2O –(0.5G H2 – 0.0592 × pH) – G *OH Among them, ΔG1 ORR is the reaction energy of O2+*+H2O+e – → * OOH+OH – ΔG2 ORR is * the reaction energy of OOH+e – → * O+OH – ΔG3 ORR is * the reaction energy of O+H2O+e – → * OH+OH – ΔG4 ORR is * the reaction energy of OH+e – →*+OH – G * refers to the Gibbs free energy of the REO cluster-loaded carbon-based catalyst, G *OOH 、G *O and G *OH respectively refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems, G H2O 、G H2 and G O2 respectively refer to the Gibbs free energies of H2O, H2, O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment; The specific method for calculating the ORR overpotential η ORR is as follows: η ORR = 0.402 + max(ΔG1 ORR , ΔG2 ORR , ΔG3 ORR , ΔG4 ORR ) / e Among them, ΔG1 ORR is the reaction energy of O2+*+H2O+e – → * OOH+OH – ΔG2 ORR is the reaction energy of free * OOH+e – → * O+OH – ΔG3 ORR is * the reaction energy of O+H2O+e – → * OH+OH – ΔG4 ORR is * the reaction energy of OH+e – →*+OH – ; e is the elementary charge In step S46, the adsorbed OH and free OH are calculated separately – The reaction energy ΔG of the side reaction to generate HOOH *OH→HOOH and the reaction energy ΔG2 of the main reaction to generate adsorbed O and free H2O OER The specific method is as follows: ΔG *OH→HOOH = G HOOH + G * – G *OH – [G H2O – (0.5G H2 – 0.0592 × pH)] ΔG2 OER = G *O + G H2O – G *OH – [G H2O – (0.5G H2 – 0.0592 × pH)] Among them, G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, G *OOH , G *O and G *OH respectively refer to the Gibbs free energies of the catalyst adsorbed with OOH, single-atom O, and OH systems, G HOOH , G H2O and G H2 respectively refer to the Gibbs free energies of single HOOH, H2O, and H2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment; The specific method for determining the reaction energy of the 4-step electron transfer process in Step S47 is: ΔG1 OER = G *OH – G * – [G H2O – (0.5G H2 – 0.0592 × pH)] ΔG2 OER = G *O + G H2O – G *OH – [G H2O – (0.5G H2 – 0.0592 × pH)] ΔG3 OER = G *OOH – G *O – [G H2O – (0.5G H2 – 0.0592 × pH)] ΔG4 OER = (G O2 + G* + G H2O ) – G *OOH – [G H2O – (0.5G H2 – 0.0592 × pH)] Among them, ΔG1 OER is the reaction energy of OH – +*→*OH+e – , ΔG2 OER is the reaction energy of *OH+OH – →*O+H2O+e – , ΔG3 OER is the reaction energy of *O+OH – →*OOH+e – , ΔG4 OER is the reaction energy of *OOH+OH – →O2+*+H2O+e – , G * refers to the Gibbs free energy of the REO cluster-supported carbon-based catalyst, G *OOH , G *O and G *OH respectively refer to the Gibbs free energies of the catalyst adsorbed OOH, O, and OH systems, G H2O , G H2 and G O2 respectively refer to the Gibbs free energies of H2O, H2, and O2 molecules, and pH is the hydrogen ion concentration index of the catalytic environment; The specific method for calculating the magnitude of the OER overpotential η OER is as follows: η OER = max(ΔG1 OER , ΔG2 OER , ΔG3 OER , ΔG4 OER ) / e–0.402 Among them, ΔG1 OER is the reaction energy of OH – +*→*OH+e – ΔG2 OER is the reaction energy of *OH+OH – →*O+H2O+e – ΔG3 OER is the reaction energy of *O+OH – →*OOH+e – ΔG4 OER is the reaction energy of *OOH+OH – →O2+*+H2O+e – The reaction energy, and e is the elementary charge.

2. The screening method of a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction according to claim 1, characterized in that, In Step S1, the REO crystal structure model obtained through different channels is the crystal structure website and the literature channel.

3. The screening method of a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction according to claim 1, characterized in that, In the step S2, the cluster configurations are loaded on the carbon-based material in the form of point, line, and surface contacts. The point form is O–C and RE–C, the line form is Line–C, and the surface form is Face–C; in the step S2, the formation energy ΔE of the bond formed between the cluster and the carbon substrate is calculated b The specific method is as follows: ΔE b = E * – E C – E REO Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, E C and E REO refer to the energies of the carbon-based and REO cluster molecules, respectively.

4. The screening method of a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction according to claim 1, characterized in that, In the steps S31 and S43, the specific method for calculating the adsorption energy ΔE of the catalyst for O2 is as follows: *O2 : ΔE *O2 = E *O2 – E * – E O2 Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, and E *O2 refers to the total energy of the system in which the catalyst adsorbs O2, and E O2 refers to the energy of a single O2 molecule; In the steps S32 and S42, the specific method for calculating the adsorption energy ΔE of the catalyst for H2O is as follows: *H2O : ΔE *H2O = E *H2O – E * – E H2O Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, and E *H2O refers to the energy of the system in which the catalyst adsorbs H2O, and E H2O refers to the energy of the H2O molecule.

5. The screening method of a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction according to claim 1, characterized in that, In the steps S33 and S41, the specific method for calculating the OH adsorption energy ΔE *OH is as follows: ΔE *OH = E *OH – E * – E OH Among them, E * refers to the energy of the REO cluster-loaded carbon-based catalyst, E *OH refers to the system energy of the catalyst adsorbing OH, and E OH refers to the energy of OH.

6. The screening method of a rare earth oxide cluster-loaded carbon-based model for efficiently catalyzing the oxygen electrode reaction according to claim 1, characterized in that, In the steps S34 and S44, the specific method for calculating the OH adsorption free energy ΔG *OH is as follows: ΔG *OH = G *OH – G * – (G H2O – 0.5G H2 ) Among them, G * and G *OH refer to the Gibbs free energies of the REO cluster-supported carbon-based catalyst and the system where the catalyst adsorbs OH, respectively. G H2O and G H2 refer to the Gibbs free energies of a single H2O and H2 molecule, respectively.

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