A method for constructing an efficient oxygen reduction reaction electrocatalyst in an acid-base full environment

Abstract

The present invention discloses a method for constructing an acid-base full environment high-efficiency oxygen reduction reaction electrocatalyst, which belongs to the field of catalyst technology. The present invention first constructs a pre-screening model for all ORR catalysts; according to ΔE f <0eV and ΔE b >E coh Screen the catalyst model; then according to ΔE *O2 <‑0.5eV, ΔE *O2 <ΔE *H2O , ΔE *O2 >‑1.5eV (acidic) or ΔE *OH >‑3.5eV (alkaline), ΔG *OH >0.4eV, ΔG *OH <1.6eV, ΔG *OOH→H2O2 >ΔG2 screening catalyst; finally according to η 酸 <0.8V, η 碱 The invention uses computer-based catalyst screening to conduct catalyst screening research, which has the advantages of low resource consumption, low carbon and environmental protection, high accuracy and high repeatability.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and in particular relates to a method for constructing an acid-base full-environment high-efficiency oxygen reduction reaction electrocatalyst. Background Art

[0002] The combustion of fossil fuels produces a large amount of waste gas containing carbon, nitrogen and sulfur. On the one hand, the waste gas emissions take away a lot of heat energy, resulting in energy waste; on the other hand, toxic waste gases such as CO, NO X , SO2 can cause serious environmental problems, and even non-toxic gases like CO2 can contribute to the greenhouse effect. Furthermore, traditional fossil fuels are non-renewable resources, and their increasing depletion will inevitably lead to an energy crisis. Therefore, human society urgently needs to develop new energy sources to alleviate the increasingly serious energy crisis and environmental problems.

[0003] As one of the ideal devices for efficient utilization of clean energy (hydrogen energy), hydrogen-oxygen fuel cells have the advantages of high energy conversion efficiency, high power density, clean and environmental protection, and play an important role in meeting the urgent demand for sustainable energy. However, the slow kinetics of the cathode oxygen reduction reaction (ORR) is one of the key factors hindering the widespread application of hydrogen-oxygen fuel cells. The ORR equilibrium potential in acidic / alkaline environments is 1.23V / 0.402V, respectively, that is, the reaction kinetics of ORR in alkaline environments is faster than that in acidic environments. However, acidic environments have higher power density than alkaline environments. In addition, in alkaline environments, OH - The conductivity of H + At the same time, in alkaline environments, H2 and O2 must be ultrapure, and the presence of CO2 in the gas source can lead to carbonate precipitation in the membrane. Thus, acidic and alkaline solution environments each have their own advantages, and Pt-based catalysts are currently the mainstream ORR electrocatalysts in the market for both acidic and alkaline environments. However, Pt is a precious metal, and its large-scale commercial application is severely hampered by factors such as resource scarcity, high cost, susceptibility to CO poisoning in the gas source, and low durability.

[0004] Therefore, in order to address the bottlenecks that restrict hydrogen and oxygen fuel cells, it is very necessary to design a rapid screening process for an acid-base all-round ORR diatomic catalyst with high catalytic efficiency and strong stability based on the rich resources and strong multi-electron activity characteristics of transition metal Tm, combined with the high atomic dispersion rate, active site utilization and strong synergistic effect of diatomic catalysts. Summary of the Invention

[0005] Existing technologies are based on a large number of experimental attempts. Due to certain unknowns, they lead to waste of human, material, financial and other resources, and face many challenges such as unclear catalytic mechanisms. In response to the shortcomings of existing technologies, the present invention provides a method for constructing an efficient oxygen reduction reaction electrocatalyst in acid-base full environments. Based on first-principles theoretical research, a screening method for predicting high-performance acid-base full-environment ORR catalyst models is provided to explore the catalytic mechanism and provide effective guidance for experimental synthesis.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] One of the purposes of the present invention is to provide a method for constructing an efficient oxygen reduction reaction electrocatalyst in an acid-base full environment, the method being a screening method for N-coordinated bimetallic atom-coordinated graphene-doped catalyst, comprising the following steps:

[0008] (1) Using VESTA, we constructed a pre-screening model for all ORR catalysts with different bimetallic combinations and different N coordination conditions, and optimized the structures based on first principles.

[0009] (2) Calculate the formation energy ΔE of the pre-screening model f and binding energy ΔE b According to ΔE f <0eV and ΔE b >E coh (Metal cohesive energy) Screening of stable catalyst models;

[0010] (3) Construct the adsorption model of the catalyst for O2 under different adsorption modes and optimize the structure (select the adsorption model with the lowest energy) to calculate the adsorption energy of the catalyst for O2 according to Screening catalyst models to ensure effective adsorption and activation of O2 by the catalyst;

[0011] (4) Construct a catalyst adsorption model for H2O and optimize the structure to calculate the adsorption energy of the catalyst for H2O In order to avoid the catalyst from being deactivated by the solvent and ensure the recycling of the catalyst, Screening catalyst models with weak or no H2O adsorption;

[0012] (5) The catalyst model is divided into two environments: acidic (pH = 0) and alkaline (pH = 14):

[0013] a. Acidic environment: According to the Sabatier principle, too strong O2 adsorption will make it difficult to desorb the product. Screening for catalysts with appropriate oxygen adsorption, if Then consider the possibility of using O2 as a ligand to modify the catalyst and proceed to step (3) to continue screening;

[0014] b. Alkaline environment: Excessive OH adsorption may deactivate the catalyst, making the catalytic cycle difficult. Construct a catalyst adsorption model for OH and optimize the structure to calculate the OH adsorption energy ΔE *OH , according to ΔE *OH >-3.5eV to screen catalysts with appropriate OH adsorption, if ΔE *OH <-3.5eV indicates that OH is difficult to desorb, so OH is used as a ligand and the process continues in step (3) for further screening.

[0015] (6) Considering the influence of zero-point vibrational energy and entropy on Gibbs free energy, further calculations are performed on the OH adsorption model to calculate the OH adsorption free energy ΔG *OH , according to ΔG *OH >0.4eV to screen catalysts with relatively high catalytic activity; if ΔG *OH <0.4eV, η must be greater than 0.8V, the catalyst does not have high activity, and in an acidic environment, the possibility of O2 as a ligand can be considered, while in an alkaline environment, the possibility of OH as a ligand can be considered, and the process goes to step (3) to continue screening;

[0016] (7) According to ΔG *OH <1.6eV for screening catalysts, if ΔG *OH >1.6eV, according to η and ΔG *OH The volcano curve shows that η must be greater than 0.8V, indicating that the catalyst has a weak ability to adsorb oxygen, a small ability to activate O2, and a low catalytic activity. Therefore, this part of the catalyst is discarded.

[0017] (8) The side reaction H2O2 will corrode the catalyst and affect its durability. The possibility of generating H2O2 should be minimized. Calculate the Gibbs free energy ΔG of OOH→H2O2. *OOH→H2O2 And the reaction energy ΔG2 of the second electronic step of the main reaction, according to Screening of catalysts Screening of catalysts with low incidence of side reactions;

[0018] (9) Calculate the overpotential η, according to η 酸 <0.8V, η 碱 <0.8V for screening highly efficient oxygen reduction reaction electrocatalysts in all acid-base environments.

[0019] Furthermore, the formation energy ΔE in step (2) f The calculation formula is shown in Eq.01; the binding energy ΔE b The calculation formula is shown in Eq.02 to Eq.03:

[0020]

[0021]

[0022]

[0023] in and E gra They refer to the system energy of the NC coordination environment and the double Tm atoms to construct the doped graphene-type diatomic catalyst and the defect-free graphene Gra, respectively. C and μ N They refer to the system energy of a single C atom and 1 / 2 N2 molecule in graphene Gra, respectively. and They refer to the energies of the monoatomic metal Tm1 and Tm2, ​​respectively; and They refer to the system energies when NC-coordinated dual Tm atoms cooperatively doped graphene catalysts have Tm1 and Tm2 vacancy defects.

[0024] Furthermore, the adsorption energy of the catalyst for O2 in step (3) is The calculation formula is shown in Eq.04:

[0025]

[0026] in Refers to the total energy of the system in which the catalyst adsorbs O2, E O2 It refers to the energy of a single O2 molecule.

[0027] Furthermore, the adsorption energy of the catalyst for H2O in step (4) is The calculation formula is shown in Eq.05:

[0028]

[0029] in It refers to the total energy of the system in which the catalyst adsorbs H2O. It refers to the energy of a single H2O molecule.

[0030] Furthermore, the OH adsorption energy ΔE in step (5) *OH The calculation formula is shown in Eq.06:

[0031]

[0032] in It refers to the total energy of the system in which the catalyst adsorbs OH, E OH It refers to the energy of a single OH.

[0033] Furthermore, the OH adsorption free energy ΔG in step (6) *OH The calculation formula is shown in Eq.07:

[0034]

[0035] in and They refer to the Gibbs free energy of the system with catalyst adsorbing OH and the system with catalyst alone, and are the Gibbs free energies of a single H2O and H2 molecule, respectively.

[0036] Furthermore, the Gibbs free energy ΔG of OOH→H2O2 in step (8) is *OOH→H2O2 The calculation formulas for the reaction energy ΔG2 of the second electronic step of the main reaction are shown in Eq.08 and Eq.09:

[0037]

[0038]

[0039] in and are the Gibbs free energy of the system where the catalyst adsorbs OOH and O, respectively. It refers to the Gibbs free energy of a single H2O2 molecule.

[0040] Furthermore, in step (9) 酸 and η 碱 The calculation formulas are shown in Eq.10 to Eq.12:

[0041] ΔG=ΔE DFT +ΔZPE–TΔS+ΔG U +ΔG pH Eq.10;

[0042] η 酸 =1.23V+[ΔG1,ΔG2,ΔG3,ΔG4] max / e Eq.11;

[0043] η 碱 =0.402V+[ΔG1,ΔG2,ΔG3,ΔG4] max / e Eq.12;

[0044] where ΔE DFT refers to the reaction energy calculated based on DFT, ΔZPE and ΔS refer to the changes in zero-point vibrational energy and entropy before and after the reaction, respectively, T refers to temperature, and ΔG U and ΔG pH They refer to the effects of potential and pH on the reaction free energy ΔG, respectively.

[0045] Furthermore, the ΔG U and ΔG pHThe calculation formulas are shown in Eq.13 and Eq.14:

[0046] ΔG U =-neU Eq.13;

[0047] ΔG pH =k B T×ln10×pH Eq.14;

[0048] Where n refers to the number of electron transfers, U refers to the applied potential, and k B Refers to the Boltzmann constant.

[0049] Other catalysts can be screened according to this method.

[0050] Beneficial effects of the present invention:

[0051] (1) The present invention conducts catalyst screening research based on high-performance computers. Unlike pure experiments that consume a lot of resources and emit "three wastes", this invention consumes very few resources and has no pollution emissions, and has the advantages of being low-carbon and environmentally friendly.

[0052] (2) The present invention comprehensively considers all possible situations of the catalyst system and fully covers potential configurations. This is different from blind trial and error in experiments and is conducive to avoiding the omission of high-performance catalysts.

[0053] (3) The present invention adopts progressive screening, which is different from the inefficient blind trial and error of pure experiments. It overcomes the shortcomings of large resource consumption and long research cycle, and is conducive to narrowing the screening range and quickly identifying potential high-performance catalysts.

[0054] (4) The present invention is based on first principles calculation research, which is different from the shortcomings of experiments such as large randomness and low repeatability, and has the characteristics of high accuracy and high repeatability.

[0055] (5) The present invention studies catalysts at the atomic scale and reveals the catalytic pathway and mechanism of catalysts from a microscopic perspective, filling the gap in the lack of clear experimental mechanisms of catalysts and being conducive to guiding experimental synthesis and further promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0057] Figure 1 Flow chart for screening high-efficiency oxygen reduction reaction catalysts in all acid-base environments. DETAILED DESCRIPTION

[0058] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the embodiments.

[0059] Example 1

[0060] Take ZnCoN6 doped graphene catalyst (ZnCoN6@Gra) as an example:

[0061] (1) Constructing a pre-screening model for ZnCoN6@Gra catalysts using VESTA and optimizing the structure based on first principles;

[0062] (2) Calculation of the formation energy ΔE of ZnCoN6@Gra f = -3.34eV and binding energy ΔE b1 =1.62eV(E coh1 =1.35eV), ΔE b2 =4.71eV(E coh2 =4.39eV); according to ΔE f <0eV and ΔE b >E coh It was found that the ZnCoN6@Gra structure was stable;

[0063] (3) Construct the adsorption model of the catalyst for O2 under different adsorption modes and optimize the structure (select the adsorption model with the lowest energy) to calculate the adsorption energy of the catalyst for O2 according to The effective adsorption and activation of O2 by ZnCoN6@Gra was demonstrated;

[0064] (4) Construct a catalyst adsorption model for H2O and optimize the structure to calculate the adsorption energy of the catalyst for H2O according to This indicates that ZnCoN6@Gra weakly adsorbs H2O, which effectively avoids the catalyst from being passivated by the solvent and ensures the recyclability of the catalyst.

[0065] (5) The catalyst model is divided into two environments: acidic (pH = 0) and alkaline (pH = 14):

[0066] a. Acidic environment: according to Consider the possibility of using O2 as a ligand modification (ZnCoN6O2@Gra), and proceed to step (3) to continue screening;

[0067] ① Construct the adsorption model of ZnCoN6O2@Gra catalyst for O2 under different adsorption modes and optimize the structure (select the adsorption model with the lowest energy) to calculate the adsorption energy of ZnCoN6O2@Gra for O2 according to ZnCoN6O2@Gra ensures the effective adsorption and activation of O2;

[0068] ②Construct the adsorption model of ZnCoN6O2@Gra for H2O and optimize the structure to calculate the adsorption energy of the catalyst for H2O according to This indicates that ZnCoN6O2@Gra weakly adsorbs H2O, which effectively avoids the catalyst from being passivated by the solvent and ensures the recyclability of the catalyst.

[0069] ③According to ZnCoN6O2@Gra has appropriate adsorption for oxygen;

[0070] ④ Considering the influence of zero-point vibrational energy and entropy on Gibbs free energy, further calculation of the OH adsorption model is performed to calculate the OH adsorption free energy ΔG *OH =1.12eV, according to ΔG *OH >0.4eV, it can be seen that ZnCoN6O2@Gra is a catalyst with relatively high catalytic activity.

[0071] ⑤ According to ΔG *OH Screening at <1.6eV shows that ZnCoN6O2@Gra has a strong oxygen activation effect and high catalytic activity;

[0072] ⑥Calculate the Gibbs free energy ΔG of OOH→H2O2 *OOH→H2O2 =-0.60eV, the reaction energy of the second electronic step of the main reaction ΔG2 =-1.76eV, according to It can be seen that ZnCoN6O2@Gra has a low side reaction rate;

[0073] b. Alkaline environment: Excessive OH adsorption may deactivate the catalyst, making the catalytic cycle difficult. Construct a catalyst adsorption model for OH and optimize the structure to calculate the OH adsorption energy ΔE *OH =-3.84eV, according to ΔE *OH <-3.5eV indicates that OH is difficult to desorb, so OH is used as a ligand (ZnCoN6OH@Gra) and the process continues in step (3).

[0074] ① Construct the adsorption model of ZnCoN6OH@Gra catalyst for O2 under different adsorption modes and optimize the structure (select the adsorption model with the lowest energy) to calculate the adsorption energy of ZnCoN6OH@Gra for O2 according to ZnCoN6OH@Gra ensures effective adsorption and activation of O2;

[0075] ②Construct the adsorption model of ZnCoN6OH@Gra for H2O and optimize the structure to calculate the adsorption energy of the catalyst for H2O according to This indicates that ZnCoN6OH@Gra weakly adsorbs H2O, which effectively avoids the catalyst from being passivated by the solvent and ensures the recyclability of the catalyst.

[0076] ③According to ZnCoN6OH@Gra has appropriate adsorption for oxygen;

[0077] ④ Considering the influence of zero-point vibrational energy and entropy on Gibbs free energy, further calculation of the OH adsorption model is performed to calculate the OH adsorption free energy ΔG *OH =0.50eV, according to ΔG *OH >0.4eV, it can be seen that ZnCoN6OH@Gra is a catalyst with relatively high catalytic activity.

[0078] ⑤ According to ΔG *OH Screening at <1.6eV shows that ZnCoN6OH@Gra has a strong oxygen activation effect and high catalytic activity;

[0079] ⑥Calculate the Gibbs free energy ΔG of OOH→H2O2 *OOH→H2O2 =-0.18eV, the reaction energy of the second electronic step of the main reaction ΔG2 =-1.67eV, according to It can be seen that ZnCoN6OH@Gra has a low incidence of side reactions;

[0080] (6) Calculate the overpotential η, η 酸 ≤0.54V,η 碱 <0.73V, according to η 酸 <0.8V, η 碱 <0.8V, it was found that ZnCoN6@Gra is an efficient oxygen reduction reaction electrocatalyst in all acid-base environments.

[0081] Comparative Example 1

[0082] 1. Synthesis of transition metal-doped carbon-based diatomic catalysts using precursor strategy

[0083] 2-Methylimidazole 2-MeIm and zinc nitrate Zn(NO3)2 are mixed in an appropriate amount of methanol CH3OH solvent at a mass ratio of 1:2 to prepare ZIF8 solution. Then, a transition metal acetylacetonate compound Tm1(acac) with an equal mass to zinc nitrate is added. X and Tm2(acac) X , stirred for 0.5 hours, and then transferred to a polytetrafluoroethylene hydrothermal synthesis reactor, heated to 120°C and kept warm for 4 hours. The precipitate was obtained by high-speed centrifugation, washed with methanol CH3OH, and then vacuum dried at 60°C for 12 hours to obtain encapsulated Tm(acac) XThe precursor Tm1Tm2@ZIF8.

[0084] The prepared precursor, Tm1Tm2@ZIF8, was placed in a tube furnace and heated to 918°C (slightly above the boiling point of Zn, 907°C, to evaporate Zn while leaving behind the high-boiling transition metal Tm) at a rate of 5°C / min under flowing N2. The temperature was maintained for 2 hours and then furnace-annealed to room temperature. The powder was then acid-washed with 0.5 mol H2SO4 for 2 hours at room temperature to remove potential large-particle metal matter. Finally, the powder was centrifuged and washed with ultrapure water and vacuum-dried at 60°C for 12 hours to obtain the transition-metal-doped porous carbon-based diatomic catalyst.

[0085] 2. Characterization of microscopic phase information of synthetic catalysts using modern analytical techniques

[0086] The BET surface area and pore size distribution were measured using a nitrogen adsorption instrument. The structure and phase of the synthesized catalyst samples were determined using X-ray diffractometers. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to observe the microstructure and morphology. Energy dispersive X-ray spectroscopy (EDS) was used to determine the content and distribution of various elements in the synthesized catalysts. Furthermore, inductively coupled plasma mass spectrometry (ICP-MS) was used to precisely determine the transition metal content. These tests and analyses provide comprehensive microscopic phase information for the catalysts.

[0087] High-angle annular dark-field scanning electron microscopy (HAADF-STEM) and selected area electron diffraction (SAED) provide further information on the active center configuration of the synthesized catalyst. X-ray photoelectron spectroscopy (XPS) analyzes the active center configuration elements and their valence states in the catalyst samples. X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine structure (EXAFS) characterize the coordination relationships of the active center configuration. These combined characterizations provide comprehensive information on the Tm active site and the NC coordination environment.

[0088] 3. In situ testing of ORR catalytic performance and mechanism using electrochemical spectroscopy

[0089] A 5 mg sample of the catalyst was dispersed in a mixture of 480 μL of ethanol, 480 μL of H₂O, and 40 μL of a 5% ethanolic solution of Nafion (Nafion) and degraded by sonication for 0.5 h. The catalyst was then dropped onto a polished glassy carbon rotating disk electrode (RDE) or rotating disk ring electrode (RRDE) with a diameter of 5 mm and dried at room temperature. The catalyst loading was approximately 0.5 mg / cm². 2 .

[0090] The test was conducted at room temperature using a three-electrode system with acidic and alkaline environments: the electrolytes were 0.1 M HClO₄ and 0.1 M KOH in saturated N₂ / O₂ aqueous solutions, respectively; the reference electrode was a saturated calomel electrode (SCE); and the counter electrode was a carbon electrode. All measured potentials were converted to reversible hydrogen electrode potentials (RHE) using Equation (1).

[0091] E RHE =E SCE +0.059×pH+0.2412 V (1);

[0092] First, perform cyclic voltammetry (CV) scanning to calculate the double layer capacitance C dl and electrochemical specific surface area ECSA; then linear sweep voltammetry LSV scan was performed to obtain the ORR onset potential E onset , half-wave potential E 1 / 2 The electrocatalytic ORR overpotential η was derived from the limiting diffusion current density (DLCD). The Tafel slope and rate-limiting step (RDS) were determined by fitting the LSV curve. The Nyquist plot, derived from electrochemical impedance spectroscopy (EIS), yielded the charge transfer resistance (Rct). Finally, the catalyst's turnover frequency (TOF) was investigated by measuring CV curves in neutral phosphate-buffered saline (PBS). Cyclic and potentiostatic durability tests were used to analyze the catalyst's stability and durability.

[0093] The number of electron transfers n during the ORR process is calculated from the slope of the Koutecky-Levich (KL) curve: -1 =j k -1 +(Bω 1 / 2 ) -1 , B=0.62nFC0D0 2 / 3 V -1 / 6 (2);

[0094] In formula (2), j k and j represent the kinetic control current density and the measured total reaction current density under constant potential, respectively; ω is the rotation rate of the disk electrode; F is the Faraday constant (96485 C / mol); and C0 is the volume concentration of O2 (1.2×10 - 6 mol / cm 3 , D0 is the diffusion coefficient of O2 in 0.1M HClO4 or 0.1M KOH solution, 1.9×10 -5 cm 2 / s, V represents the viscosity of the electrolyte 0.01cm 2 The yield of the side reaction H2O2 was calculated based on the electron transfer number n according to the relationship between the electron transfer number n and the hydrogen peroxide H2O2 yield shown in formula 3.

[0095] n=4i d / (i d +i r / N), H2O2%=200i d / (i d ×N+i r ) (3);

[0096] i d is the disk current density, i r is the ring current density, and the Pt ring current collection efficiency N=0.37.

[0097] Comparative Example 1 has the following disadvantages:

[0098] ① The existing technology is to first conduct experimental synthesis, then characterize the catalyst, and finally perform electrochemical performance testing. Due to its unknown nature, the performance of the synthesized catalyst may be insufficient, resulting in a waste of time, energy, material resources and other resources. ② The experimental process has many steps and many process condition variables, resulting in low repeatability of the experimental results. ③ The experimental cycle is long, covering three major sections: catalyst preparation, catalyst characterization, and catalytic performance testing. In addition, the subsequent optimization of the process and improvement of performance also face the disadvantage of a long cycle. ④ There are many experimental consumables and large emissions of "three wastes". Including two major sections: catalyst preparation and catalytic performance testing. In addition, the subsequent optimization of the process and improvement of performance also face the challenges of many experimental research consumables and large emissions of "three wastes". ⑤ The cost of experimental research is high, covering three major sections: catalyst preparation, catalyst characterization, and catalytic performance testing. In particular, catalyst characterization is time-consuming, labor-intensive and costly.

[0099] This invention, based on first-principles theoretical calculations, offers advantages such as low resource consumption, low time cost, zero pollution emissions, and high repeatability. It provides precise guidance for experimental synthesis, thereby safeguarding the promotion of hydrogen-oxygen fuel cells. It also effectively enhances the high-value-added utilization of mineral resources and the technological competitiveness of the catalysis industry, helping to promote the application of new energy vehicles, comprehensively promoting the optimization of the energy industry structure, and ensuring energy security.

[0100] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for constructing an acid-base full-environment high-efficiency oxygen reduction reaction electrocatalyst, characterized in that: The method is a method for screening N-coordinated bimetallic atoms cooperatively doped graphene catalysts, comprising the following steps: (1) Build a pre-screening model for all ORR catalysts; (2) Calculate the formation energy ΔE of the pre-screening model f and binding energy ΔE b According to ΔE f <0eV and ΔE b >E coh Screening catalyst models; (3) Construct a catalyst adsorption model for O2 and calculate the adsorption energy of the catalyst for O2 according to Screening catalyst models; (4) Construct a catalyst adsorption model for H2O and calculate the adsorption energy of the catalyst for H2O according to Screening catalyst models; (5) The catalyst model is divided into two environments: acidic and alkaline: a. Acidic environment: according to Screening catalysts, if Go to step (3) to continue screening; b. Alkaline environment: Construct a catalyst adsorption model for OH and calculate the OH adsorption energy ΔE *OH , according to ΔE *OH >-3.5eV to screen catalysts, if ΔE *OH <-3.5eV, proceed to step (3) to continue screening; (6) Calculation of OH adsorption free energy ΔG *OH , plot the overpotential η versus ΔG *OH The volcano curve diagram, according to ΔG *OH >0.4eV to screen catalysts; if ΔG *OH <0.4eV, proceed to step (3) to continue screening; (7) According to ΔG *OH <1.6eV for screening catalysts, if ΔG *OH >1.6eV, discard this part of the catalyst; (8) Calculate the Gibbs free energy ΔG of OOH→H2O2 *OOH→H2O2 And the reaction energy ΔG2 of the second electronic step of the main reaction, according to screening of catalysts; (9) Calculate the overpotential η, according to η 酸 <0.8V, η 碱 <0.8V for screening highly efficient oxygen reduction reaction electrocatalysts in all acid and base environments; The formation energy ΔE in step (2) f The calculation formula is shown in Eq.01; the binding energy ΔE b The calculation formula is shown in Eq.02 to Eq.03: in and E gra They refer to the system energy of the NC coordination environment and the double Tm atoms to construct the doped graphene-type diatomic catalyst and the defect-free graphene Gra, respectively. C and μ N They refer to the system energy of a single C atom and 1 / 2 N2 molecule in graphene Gra, respectively. and They refer to the energies of the monoatomic metal Tm1 and Tm2, ​​respectively; and They refer to the system energy when NC coordinated dual Tm atoms cooperatively doped graphene catalysts have Tm1 and Tm2 vacancy defects; The adsorption energy of the catalyst for O2 in step (3) The calculation formula is shown in Eq.04: in It refers to the total energy of the system in which the catalyst adsorbs O2. It refers to the energy of a single O2 molecule; Adsorption energy of the catalyst for H2O in step (4) The calculation formula is shown in Eq.05: in It refers to the total energy of the system in which the catalyst adsorbs H2O. It refers to the energy of a single H2O molecule; The OH adsorption energy ΔE in step (5) *OH The calculation formula is shown in Eq.06: in It refers to the total energy of the system in which the catalyst adsorbs OH, E OH It refers to the energy of a single OH; The OH adsorption free energy ΔG in step (6) *OH The calculation formula is shown in Eq.07: in and They refer to the Gibbs free energy of the system with catalyst adsorbing OH and the system with catalyst alone, and are the Gibbs free energies of single H2O and H2 molecules, respectively; Gibbs free energy ΔG of OOH→H2O2 in step (8) *OOH→H2O2 The calculation formulas for the reaction energy ΔG2 of the second electronic step of the main reaction are shown in Eq.08 and Eq.09: in and are the Gibbs free energy of the system where the catalyst adsorbs OOH and O, respectively. It refers to the Gibbs free energy of a single H2O2 molecule; Step (9) 酸 and η 碱 The calculation formulas are shown in Eq.10 to Eq.12: ΔG=ΔE DFT +ΔZPE–TΔS+ΔG U +ΔG pH Eq.10; or 酸 =1.23V+[ΔG1,ΔG2,ΔG3,ΔG4] max / e Eq.11; or 碱 =0.402V+[ΔG1,ΔG2,ΔG3,ΔG4] max / e Eq.12; where ΔE DFT refers to the reaction energy calculated based on DFT, ΔZPE and ΔS refer to the changes in zero-point vibrational energy and entropy before and after the reaction, respectively, T refers to temperature, and ΔG U and ΔG pH They refer to the effects of potential and pH on the reaction free energy ΔG, respectively.

2. The method for constructing an acid-base full-environment high-efficiency oxygen reduction reaction electrocatalyst according to claim 1, characterized in that: The ΔG U and ΔG pH The calculation formulas are shown in Eq.13 and Eq.14: ΔG U =-neU Eq.13; ΔG pH =k B T×ln10×pH Eq.14; Where n refers to the number of electron transfers, U refers to the applied potential, and k B Refers to the Boltzmann constant.

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