Irradiation damage influence method of carbon-based material AB double-layer graphene

Abstract

The invention discloses an irradiation damage influence method of carbon-based material AB double-layer graphene, and particularly relates to the technical field of material science and electronics, and the method comprises the steps of S1, microstructure model construction, S2, fast neutron irradiation simulation, S3, external electric field application, S4, microstructure parameter statistics, S5, energy band structure calculation, S6, elastic constant and Young's elastic modulus calculation, and S7, optical property calculation. According to the method, the irradiation damage influence of the AB double-layer graphene of the carbon-based material under the conditions of fast neutron irradiation, an external electric field, different irradiation sources, temperature change, existence of defects and the like can be comprehensively researched, and the influence of various factors on the microstructure, the energy band structure, the Young's elastic modulus and the optical property of the AB double-layer graphene can be analyzed; theoretical support is provided for design and optimization of a carbon-based device, and meanwhile, a reference basis can be provided for irradiation protection and material performance improvement.

Description

Technical Field

[0001] The invention relates to the fields of material science and electronic technology, and more specifically to a method for influencing radiation damage of carbon-based material AB double-layer graphene. Background Art

[0002] In the fields of materials science and electronic technology, carbon-based materials, especially graphene, have attracted much attention due to their excellent performance. As a two-dimensional carbon-based material with excellent electrical, mechanical and thermal properties, graphene has shown great application potential in many fields. AB double-layer graphene, as a special structure of graphene, has unique electronic properties and interlayer interactions, and has important application prospects in carbon-based electronic devices. In practical applications, carbon-based materials are often affected by external factors such as radiation and electric fields. Fast neutron irradiation and external electric fields will change the material structure and properties.

[0003] At present, there have been some studies on the performance of AB double-layer graphene under a single factor, but there is a lack of in-depth understanding of the performance changes under the combined action of multiple factors. For example, there is limited research on the effects of different radiation sources, temperature changes and material defects on it under radiation and electric fields. In order to better understand and utilize the performance of AB double-layer graphene, there is an urgent need for methods to study the effects of radiation damage on carbon-based materials AB double-layer graphene, so as to improve the performance and reliability of carbon-based devices and provide a theoretical basis for their design, optimization and radiation protection. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, the present invention provides a method for controlling the radiation damage of carbon-based material AB double-layer graphene to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for irradiation damage of carbon-based material AB double-layer graphene, which specifically comprises the following steps: S1, constructing a microstructure model, constructing an AB double-layer graphene microstructure model, wherein the AB double-layer graphene microstructure model is composed of 4×4 double-layer graphene super monomers, and the Z-direction height is set to 20Å, wherein the double-layer graphene super monomer has 64 atoms; S2. Fast neutron irradiation simulation. In molecular dynamics, the irradiation process is simulated by increasing the speed of a single C atom. The speed direction is along the negative direction of the Z axis. The irradiation process is simplified to carbon atoms (C) absorbing energy, thereby increasing the atomic kinetic energy and causing lattice disturbance. The fast neutron energy is set to 1MeV and the irradiation dose is 1×10 13 n / cm², the relaxation step size was set to 1 fs, and 10000 steps (10 ps) of relaxation were performed under NVE to reach equilibrium; The formula for calculating the energy (T) transferred by the incident neutron is: , ,in, is the incident neutron energy, T is the energy transferred by the incident neutron, r is the energy loss in the inelastic collision, and A is the atomic mass of the recoil atom; S3, applied electric field, applied electric field (−0.1 V / Å to −0.4 V / Å) to the initial structure, studied the effect of electric field on the microstructure, band structure, Young's elastic modulus and optical properties of the system, and selected the electric field strength of −0.2 V / Å for subsequent research; S4. Statistical microstructural parameters, including the coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF of AB bilayer graphene before and after irradiation, analyze the effects of fast neutron irradiation and applied electric field on the microstructure, and infer the relationship between the configuration change and surface ripple generation of AB bilayer graphene and the irradiation damage of carbon-based devices; S5. Calculate the energy band structure of the AB bilayer graphene system before and after irradiation, analyze the effects of fast neutron irradiation and applied electric field on the energy band structure, including the changes in band gap type, band gap value and electrostatic potential, and explore the effects of applied electric field on the accurate regulation of the band gap of AB bilayer graphene; S6. Calculate the elastic constants and Young's elastic modulus, and calculate the elastic constants (C 11 , C 12 , C 22 , C 66 ), the mechanical stability of the system is determined according to the Born-Huang criteria, and the effects of fast neutron irradiation and applied electric field on the Young's modulus of AB bilayer graphene, as well as the effects on phonon group velocity, thermal conductivity and carrier mobility are analyzed; Among them, the formula for calculating the Young's elastic modulus (Y) of the two-dimensional material hexagonal system AB double-layer graphene is: , where C 11、 C 12、 C 22 and C 66 The parameters can be read out through the calculated elasticity matrix; S7. Calculate the optical properties. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties. Calculate the complex dielectric function, light absorption coefficient and refractive index of the system. Analyze the effects of fast neutron irradiation and applied electric field on the optical properties of AB bilayer graphene, including the changes in the real and imaginary parts of the dielectric function, the light absorption coefficient and the parallel and perpendicular components of the refractive index. The formula for calculating the complex dielectric function is: ,in, and are the real and imaginary parts of the dielectric function, ω is the photon frequency; calculate The formula is: (ω)=1+ p ; calculate The formula is: The formula for light absorption coefficient is: ,in, is the speed of light in a vacuum; Refractive index formula: n(ω) ,in, and are the real and imaginary parts of the dielectric function, respectively.

[0006] Preferably, in step S1, when constructing the AB bilayer graphene microstructure model, the Perdew-Burke-Ernzerhof approximation in the generalized gradient approximation of the projector augmented wave in the VASP tool is used to calculate the electronic structure, optical properties and mechanical properties of the AB bilayer graphene, and optB88 vdW is used as a function to help consider long-range van der Waals interactions.

[0007] Preferably, in step S1, a 5×5×1 k-point grid centered on Γ is used in the calculation of structural optimization and mechanical properties, and a 7×1×1 k-point grid with higher accuracy is used for self-consistent and non-self-consistent calculations except for optical properties. When calculating optical properties, a 13×13×1 K-point grid centered on Γ is used for Brillouin zone sampling, and the plane wave cutoff energy is set to 500 eV, and the convergence values ​​of the total electron energy and ion force are 1.0×10 -6 eV, 0.01eV / Å, ISMEAR=0.

[0008] Preferably, in step S5, when performing the energy band calculation, a 20 k-point grid is used along the Brillouin zone of the path G - M - K - G.

[0009] Preferably, in step S4, when analyzing the effects of fast neutron irradiation and an applied electric field on the microstructure of AB double-layer graphene, the greater the fast neutron irradiation energy, the greater the impact on the microstructure, and the effect of the applied electric field on the microstructure of the system is limited, but fast neutron irradiation under an applied electric field will cause further changes in the average interlayer spacing and configuration of the system, and the superposition of the electric field and irradiation will cause the symmetry and periodicity of the system to be further reduced.

[0010] Preferably, in step S5, when analyzing the effects of fast neutron irradiation and applied electric field on the band structure of AB double-layer graphene, the effect of fast neutron irradiation on the band structure of AB double-layer graphene is limited, and the band gap will open slightly after irradiation. The effect of fast neutron irradiation on the band gap value under an applied electric field is very different from the effect on the microstructure. Further changes in the average interlayer spacing of the system under applied electric field irradiation lead to the diversity of the system configuration, and the diversity of configuration ultimately leads to the diversity of the system band structure. Under the condition of a certain fast neutron dose, the type and size of the band gap of the system after applied electric field irradiation depends on the intensity of the applied electric field and the size of the irradiation energy. In a fast neutron irradiation environment, the accurate regulation of the band gap of AB double-layer graphene by an applied electric field will fail.

[0011] Preferably, in step S6, when analyzing the effects of fast neutron irradiation and applied electric field on the Young's modulus of AB double-layer graphene, the Y of the AB double-layer graphene decreases monotonically with the increase of fast neutron irradiation energy, and the fast neutron irradiation has a certain negative impact on the phonon group velocity, thermal conductivity and carrier mobility of the AB double-layer graphene. Fast neutron irradiation under an applied electric field will cause the Y of the AB double-layer graphene to decrease faster than that of fast neutron irradiation alone. Fast neutron irradiation under an applied electric field will have a greater negative impact on the phonon group velocity, thermal conductivity and carrier mobility of the AB double-layer graphene than that of fast neutron irradiation alone.

[0012] Preferably, in step S7, when analyzing the effects of fast neutron irradiation and an applied electric field on the optical properties of AB double-layer graphene, the change in the optical properties of the AB double-layer graphene system caused by fast neutron irradiation is mainly due to the change in the system configuration induced by the irradiation, and fast neutron irradiation under an applied electric field will also cause changes in the optical properties of the system. This is because, on the one hand, it is due to the effect of the applied electric field on the system, and on the other hand, fast neutron irradiation under an applied electric field will induce changes in the system configuration, which in turn jointly lead to changes in the optical properties of the system.

[0013] Preferably, the change in the configuration of AB double-layer graphene induced by fast neutron irradiation and the appearance of induced surface ripples are two main reasons for the changes in various properties of the system. The appearance of surface ripples and the change in configuration may be two important reasons for the performance degradation and damage of carbon-based devices. The uncertainty change in the type and size of the band gap of AB double-layer graphene under fast neutron irradiation with an external electric field may be one of the reasons for the performance degradation and permanent damage of carbon-based devices in practical applications. In addition, regardless of whether an external electric field is applied, fast neutron irradiation with an energy difference of one order of magnitude (1×10¹³n / cm² dose) has significant differences in the effects on various properties of AB double-layer graphene.

[0014] The present invention also includes the following different methods, which specifically include the following steps: S8. Introduce other types of radiation sources, such as protons, alpha particles and heavy ions, to study their effects on the radiation damage of AB bilayer graphene, specifically including the following steps: S8.1. Construct a microstructure model of AB bilayer graphene under different irradiation sources. For each irradiation source, consider its interaction characteristics with carbon atoms and adjust the model parameters to more accurately reflect the initial state under different irradiation conditions. For example, for proton irradiation, it may be necessary to consider the impact effect of the smaller mass and higher velocity of protons on the graphene structure; for heavy ion irradiation, it is necessary to consider the strong local disturbance caused by the high energy and larger mass of heavy ions; S8.2. In molecular dynamics, simulate the irradiation process of different irradiation sources, set the corresponding irradiation energy and dose, and determine the reasonable irradiation energy range and dose level according to the physical properties of different irradiation sources. For example, the irradiation energy of protons can be gradually increased from a low value to study its effect on graphene at different energies. The energy of alpha particles is usually high, and the dose needs to be adjusted appropriately to avoid excessive damage to the structure. At the same time, record the motion trajectory and energy transfer process of carbon atoms under different irradiation sources. S8.3. Statistical analysis of the microstructure parameters of AB bilayer graphene before and after irradiation, and analysis of the effects of different irradiation sources on the microstructure. In addition to the original parameters such as coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF, the carbon atom displacement distribution and chemical bond changes caused by different irradiation sources can be further analyzed. For example, for heavy ion irradiation, more obvious local structural deformation and chemical bond breakage may be observed; for α-particle irradiation, structural damage in a specific direction may occur; S8.4. Calculate the band structure of the AB bilayer graphene system before and after irradiation, analyze the effects of different irradiation sources on the band structure, and compare the band gap type, band gap value changes, and electrostatic potential distribution under different irradiation sources. It may be found that the band structure changes caused by different irradiation sources have unique rules. For example, proton irradiation may cause a small band gap change, but has a specific effect on the shape and distribution of the energy band; heavy ion irradiation may cause a large band gap change and disorder of the band structure. S8.5. Calculate the elastic constants of the system before and after irradiation, analyze the effect of different irradiation sources on the Young's modulus of AB bilayer graphene, and evaluate the change of Young's modulus by calculating parameters such as C11, C12, C22, and C66 under different irradiation sources. Different irradiation sources may have different effects on the elastic modulus. For example, α-particle irradiation may significantly reduce the elastic modulus, while proton irradiation has a relatively small effect. At the same time, analyze the effect on phonon group velocity, thermal conductivity, and carrier mobility, and explore the change patterns of these properties under different irradiation sources; S8.6. Use the RPA method to perform DFT calculations on the optical properties, analyze the effects of different irradiation sources on the optical properties of AB bilayer graphene, calculate the complex dielectric function, light absorption coefficient and refractive index of the system under different irradiation sources, and study the differences with fast neutron irradiation. For example, heavy ion irradiation may lead to a significant increase in the light absorption coefficient, while proton irradiation may have a more obvious effect on the refractive index. At the same time, analyze the reasons for the changes in optical properties under different irradiation sources and relate them to changes in the microstructure and band structure.

[0015] S9. Considering the effects of fast neutron irradiation and external electric field on AB double-layer graphene under different temperature conditions, the following steps are specifically included: S9.1. Construct a microstructure model of AB bilayer graphene at different temperatures, taking into account the thermal expansion effect of temperature on graphene and adjusting the atomic spacing and lattice parameters of the model. For example, at higher temperatures, the atomic vibration of graphene intensifies and the interlayer spacing may increase slightly. At the same time, considering the effect of temperature on the chemical bonds between carbon atoms, the bond length and bond angle may change. S9.2. Simulate fast neutron irradiation and applied electric field, record the changes of the system at different temperatures, simulate fast neutron irradiation and applied electric field at different temperatures, observe the influence of temperature on the system under irradiation and electric field, record the movement trajectory of carbon atoms, energy transfer and electric field distribution, and analyze the interaction between temperature, irradiation and electric field. For example, at higher temperatures, fast neutron irradiation may lead to more violent atomic movement and structural damage; the effect of applied electric field may be affected by temperature, resulting in changes in the electrical properties of the system; S9.3. Analyze the effects of different temperatures on the microstructure, band structure, Young's modulus and optical properties of AB bilayer graphene. For the microstructure, analyze the changes in interlayer spacing, atomic displacement and configuration caused by temperature. For the band structure, study the effects of temperature on the type and value of band gaps, as well as the changing laws of band structure under the combined effects of temperature, irradiation and electric field. For Young's modulus, evaluate the degree of influence of temperature on the modulus, as well as the synergistic effects with irradiation and electric field. For optical properties, calculate the complex dielectric function, light absorption coefficient and refractive index at different temperatures, and analyze the mechanism of the influence of temperature on optical properties. For example, higher temperatures may lead to an increase in the light absorption coefficient, and the change in refractive index may also be related to temperature. At the same time, consider the combined effects of temperature, irradiation and electric field on the performance of carbon-based devices to provide a more comprehensive theoretical basis for practical applications. S10. Combining quantum mechanical calculations and molecular dynamics simulations, a multi-scale simulation study was conducted to more accurately describe the behavior of AB bilayer graphene under irradiation and electric field, including the following steps: S10.1. Use quantum mechanics calculation methods to calculate the electronic structure and band structure of AB bilayer graphene. Use high-precision quantum mechanics calculation methods, such as density functional theory (DFT), to accurately calculate the electronic structure, band structure, and state density of graphene, taking into account the influence of long-range van der Waals interactions and external electric fields, and analyze the distribution and movement of electrons in graphene. For example, by calculating the band structure, the type and value of the band gap, as well as the regulation of the band gap by the external electric field, can be determined. At the same time, the wave function and orbital hybridization of electrons can be analyzed to understand the behavior of electrons under irradiation and electric fields. S10.2. Use molecular dynamics simulation methods to simulate the atomic motion and structural changes of AB bilayer graphene under irradiation and electric field. In molecular dynamics simulation, the effects of fast neutron irradiation and external electric field on carbon atoms are considered to simulate the motion trajectory, energy transfer and structural changes of atoms. Different force field models and simulation parameters can be used to accurately describe the mechanical behavior of graphene under irradiation and electric field. For example, through simulation, atomic displacement, interlayer spacing changes and surface ripple formation caused by irradiation can be observed; external electric field can cause changes in polarization and charge distribution of carbon atoms. At the same time, key parameters in the simulation process, such as temperature, pressure, energy, etc., are recorded for subsequent analysis. S10.3. Combine the results of quantum mechanics calculations and molecular dynamics simulations to conduct multi-scale analysis and research. Combine the electronic structure information obtained from quantum mechanics calculations with the atomic structure changes obtained from molecular dynamics simulations to conduct multi-scale analysis. For example, by analyzing the changes in the density of states of electrons under irradiation and electric fields, we can understand the excitation and transition processes of electrons. At the same time, combined with the changes in the atomic structure, we can analyze the interaction between electrons and atoms. In addition, we can study the combined effects of irradiation and electric fields on the electrical, mechanical, and optical properties of graphene, and explore its application potential in carbon-based devices. Through multi-scale simulations, we can have a more comprehensive understanding of the behavior of AB bilayer graphene under irradiation and electric fields, and provide theoretical support for the design and optimization of carbon-based devices.

[0016] S11. Explore the effects of defects in AB bilayer graphene, such as vacancies and impurities, on its performance under irradiation and electric field, including the following steps: S11.1. Construct a defective AB double-layer graphene microstructure model, introduce defects of different types and concentrations into the graphene model, such as vacancy defects and impurity atoms, consider the influence of the position, type and concentration of defects on the graphene structure, and adjust the model parameters to accurately reflect the existence of defects. For example, a graphene model containing a single vacancy defect, multiple vacancy defects or impurity atoms replacing carbon atoms can be constructed. At the same time, analyze the influence of defects on the electronic structure and mechanical properties of graphene to provide a basis for subsequent simulation research; S11.2. Simulate irradiation and applied electric field to study the effect of defects on the microstructure of AB bilayer graphene. Simulate fast neutron irradiation and applied electric field on a graphene model with defects to observe the effect of defects on the graphene structure under irradiation and electric field. For example, defects may cause local atomic displacement and structural deformation, affecting the change of interlayer spacing and configuration. At the same time, analyze the effect of defects on the formation and development of surface ripples and the difference with defect-free graphene. Record the atomic motion trajectory and energy transfer process around the defects to gain a deeper understanding of the interaction between defects and irradiation and electric field. S11.3. Calculate the energy band structure of the AB bilayer graphene system with defects, analyze the effect of defects on the energy band structure, calculate the energy band structure of the graphene system with defects, and compare the difference with defect-free graphene. Defects may introduce new energy levels and state density distributions, and change the band gap type and band gap value. For example, vacancy defects may cause the band gap to increase or decrease, and impurity atoms may introduce impurity energy levels, affecting the transmission and optical properties of electrons. Analyze the effect of defects on the distribution of electrostatic potential and electron wave functions, and understand the role of defects on the movement and transition of electrons in graphene. S11.4. Calculate the elastic constants of defective systems and analyze the effect of defects on the Young's modulus of AB bilayer graphene. By calculating the elastic constants of defective graphene systems, evaluate the effect of defects on the Young's modulus. Defects may reduce the elastic modulus of graphene and affect its mechanical properties. Analyze the influence of different types and concentrations of defects on the elastic modulus, as well as the synergistic effect with irradiation and electric field. For example, under the action of irradiation and electric field, defects may lead to a further decrease in the elastic modulus, affecting the stability and reliability of carbon-based devices. S11.5. Use the RPA method to perform DFT calculations on the optical properties of defective AB bilayer graphene and analyze the effects of defects on the optical properties. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties of defective graphene systems and analyze the effects of defects on the complex dielectric function, light absorption coefficient, and refractive index. Defects may change the optical response of graphene and affect its application in optoelectronic devices. For example, vacancy defects may cause an increase or decrease in the light absorption coefficient, and impurity atoms may introduce new optical absorption peaks. At the same time, analyze the changes in optical properties under the combined effects of defects, irradiation, and electric fields to provide theoretical guidance for the design of carbon-based devices with specific optical properties.

[0017] Technical effects and advantages of the present invention: 1. The present invention takes into account the effects of multiple factors such as fast neutron irradiation, external electric field, different irradiation sources, temperature changes and defects on AB double-layer graphene. This multi-factor comprehensive analysis can more comprehensively reveal the law of performance changes of AB double-layer graphene in complex environments and provide more accurate theoretical guidance for practical applications. In addition, multi-scale research combined with quantum mechanics calculations and molecular dynamics simulations can deeply understand the behavior of AB double-layer graphene from the two levels of electronic structure and atomic motion, which helps to more accurately predict the performance changes of materials under irradiation and electric fields, and provide more powerful support for material design and optimization; 2. The present invention can provide optimization direction for the design of carbon-based devices by studying the influence of various factors on the microstructure, band structure, Young's modulus and optical properties of AB double-layer graphene. For example, suitable irradiation conditions, electric field strength and temperature range can be selected to improve the performance and stability of carbon-based devices. Moreover, understanding the damage mechanism of different irradiation sources on AB double-layer graphene can provide effective protection measures for the application of carbon-based devices in irradiated environments, which helps to improve the reliability and life of carbon-based devices and reduce maintenance costs. At the same time, studying the influence of defects on the performance of AB double-layer graphene can provide guidance for defect control in the material preparation process. By reducing or eliminating defects, the quality and performance of AB double-layer graphene can be improved, and the performance of carbon-based devices can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention. DETAILED DESCRIPTION

[0019] Embodiment 1, The present invention provides a method for the radiation damage of carbon-based material AB double-layer graphene, which specifically comprises the following steps; S1. Use the Perdew-Burke-Ernzerhof approximation in the generalized gradient approximation of the projector augmented wave in the VASP tool to construct an AB double-layer graphene microstructure model. The model consists of a 4×4 double-layer graphene supermonomer, with a Z-direction height of 20Å and a double-layer graphene supermonomer with 64 atoms. S2. In molecular dynamics, the irradiation process is simulated by increasing the speed of a single C atom along the negative direction of the Z axis, setting the fast neutron energy to 1 MeV and the irradiation dose to 1×10 13 n / cm², the relaxation step size is set to 1 fs, and 10000 steps (10 ps) of relaxation are performed under NVE to reach equilibrium. The energy transferred by the incident neutron is calculated using the formula , ,in, is the incident neutron energy, T is the energy transferred by the incident neutron, r is the energy loss in the inelastic collision, and A is the atomic mass of the recoil atom; S3. Apply an electric field to the initial structure, ranging from −0.1 V / Å to −0.4 V / Å, and select −0.2 V / Å for subsequent studies to study the effect of the electric field on the microstructure, band structure, Young's elastic modulus, and optical properties of the system; S4. Statistical analysis of the coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF of AB bilayer graphene before and after irradiation, analysis of the effects of fast neutron irradiation and applied electric field on the microstructure, and inference of the relationship between the configuration change and surface ripple generation of AB bilayer graphene and the irradiation damage of carbon-based devices; S5. Calculate the band structure of the AB bilayer graphene system before and after irradiation. When performing the band calculation, use a 20 k-point grid along the Brillouin zone of the path G - M - K - G to analyze the effects of fast neutron irradiation and applied electric field on the band structure, including the changes in band gap type, band gap value, and electrostatic potential, and explore the effect of applied electric field on the accurate regulation of the band gap of AB bilayer graphene. S6. Calculate the elastic constants (C11, C12, C22, C66) of the system before and after irradiation. Determine the mechanical stability of the system according to the Born-Huang criteria using the formula Calculate the Young's modulus (Y) of the two-dimensional material hexagonal system AB bilayer graphene, where the C11, C12, C22 and C66 parameters can be read out through the calculated elastic matrix, and analyze the effects of fast neutron irradiation and external electric field on the Young's modulus of AB bilayer graphene, as well as the effects on phonon group velocity, thermal conductivity and carrier mobility; S7. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties, calculate the complex dielectric function, light absorption coefficient and refractive index of the system, and analyze the effects of fast neutron irradiation and applied electric field on the optical properties of AB bilayer graphene, including the changes in the real and imaginary parts of the dielectric function, the light absorption coefficient and the parallel and perpendicular components of the refractive index; The formula for calculating the complex dielectric function is: ,in, and are the real and imaginary parts of the dielectric function, respectively, and ω is the photon frequency; calculate The formula is: (ω)=1+ p calculate The formula is: The formula for light absorption coefficient is: ,in, is the speed of light in a vacuum; Refractive index formula: n(ω) ,in, and are the real and imaginary parts of the dielectric function, respectively.

[0020] Embodiment 2, The present embodiment is different from the embodiment 1 in that, on the basis of the embodiment 1, other types of radiation sources, such as protons, α particles and heavy ions, are introduced to study their radiation damage effects on the AB double-layer graphene. The specific formula and algorithm are consistent, and specifically include the following steps: S8.1. Construct a microstructure model of AB bilayer graphene under different irradiation sources. For each irradiation source, consider its interaction characteristics with carbon atoms and adjust the model parameters to more accurately reflect the initial state under different irradiation conditions. For example, for proton irradiation, it may be necessary to consider the impact effect of the smaller mass and higher velocity of protons on the graphene structure; for heavy ion irradiation, it is necessary to consider the strong local disturbance caused by the high energy and larger mass of heavy ions; S8.2. In molecular dynamics, simulate the irradiation process of different irradiation sources, set the corresponding irradiation energy and dose, and determine the reasonable irradiation energy range and dose level according to the physical properties of different irradiation sources. For example, the irradiation energy of protons can be gradually increased from a low value to study its effect on graphene at different energies. The energy of alpha particles is usually high, and the dose needs to be adjusted appropriately to avoid excessive damage to the structure. At the same time, record the motion trajectory and energy transfer process of carbon atoms under different irradiation sources. S8.3. Statistical analysis of the microstructure parameters of AB bilayer graphene before and after irradiation, and analysis of the effects of different irradiation sources on the microstructure. In addition to the original parameters such as coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF, the carbon atom displacement distribution and chemical bond changes caused by different irradiation sources can be further analyzed. For example, for heavy ion irradiation, more obvious local structural deformation and chemical bond breakage may be observed; for α-particle irradiation, structural damage in a specific direction may occur; S8.4. Calculate the band structure of the AB bilayer graphene system before and after irradiation, analyze the effects of different irradiation sources on the band structure, and compare the band gap type, band gap value changes, and electrostatic potential distribution under different irradiation sources. It may be found that the band structure changes caused by different irradiation sources have unique rules. For example, proton irradiation may cause a small band gap change, but has a specific effect on the shape and distribution of the energy band; heavy ion irradiation may cause a large band gap change and disorder of the band structure. S8.5. Calculate the elastic constants of the system before and after irradiation, analyze the effect of different irradiation sources on the Young's modulus of AB bilayer graphene, and evaluate the change of Young's modulus by calculating parameters such as C11, C12, C22, and C66 under different irradiation sources. Different irradiation sources may have different effects on the elastic modulus. For example, α-particle irradiation may significantly reduce the elastic modulus, while proton irradiation has a relatively small effect. At the same time, analyze the effect on phonon group velocity, thermal conductivity, and carrier mobility, and explore the change patterns of these properties under different irradiation sources; S8.6. Use the RPA method to perform DFT calculations on the optical properties, analyze the effects of different irradiation sources on the optical properties of AB bilayer graphene, calculate the complex dielectric function, light absorption coefficient and refractive index of the system under different irradiation sources, and study the differences with fast neutron irradiation. For example, heavy ion irradiation may lead to a significant increase in the light absorption coefficient, while proton irradiation may have a more obvious effect on the refractive index. At the same time, analyze the reasons for the changes in optical properties under different irradiation sources and relate them to changes in the microstructure and band structure.

[0021] Embodiment 3, Compared with Example 1, this embodiment is different in that, based on Example 1, by considering the effects of fast neutron irradiation and external electric field on AB double-layer graphene under different temperature conditions, the specific formula and algorithm are consistent, and specifically include the following steps: S9.1. Construct a microstructure model of AB bilayer graphene at different temperatures, taking into account the thermal expansion effect of temperature on graphene and adjusting the atomic spacing and lattice parameters of the model. For example, at higher temperatures, the atomic vibration of graphene intensifies and the interlayer spacing may increase slightly. At the same time, considering the effect of temperature on the chemical bonds between carbon atoms, the bond length and bond angle may change. S9.2. Simulate fast neutron irradiation and applied electric field, record the changes of the system at different temperatures, simulate fast neutron irradiation and applied electric field at different temperatures, observe the influence of temperature on the system under irradiation and electric field, record the movement trajectory of carbon atoms, energy transfer and electric field distribution, and analyze the interaction between temperature, irradiation and electric field. For example, at higher temperatures, fast neutron irradiation may lead to more violent atomic movement and structural damage; the effect of applied electric field may be affected by temperature, resulting in changes in the electrical properties of the system; S9.3. Analyze the effects of different temperatures on the microstructure, band structure, Young's modulus and optical properties of AB bilayer graphene. For the microstructure, analyze the changes in interlayer spacing, atomic displacement and configuration caused by temperature. In the band structure, study the effects of temperature on the type and value of band gaps, as well as the changing laws of the band structure under the combined effects of temperature, irradiation and electric field. For Young's modulus, evaluate the degree of influence of temperature on the modulus, as well as the synergistic effects with irradiation and electric field. In the optical properties, calculate the complex dielectric function, light absorption coefficient and refractive index at different temperatures, and analyze the mechanism of the influence of temperature on optical properties. For example, higher temperatures may lead to an increase in the light absorption coefficient, and changes in the refractive index may also be related to temperature. At the same time, consider the combined effects of temperature, irradiation and electric field on the performance of carbon-based devices to provide a more comprehensive theoretical basis for practical applications.

[0022] Embodiment 4, The difference between this embodiment and embodiment 1 is that, based on embodiment 1, a multi-scale simulation study is performed in combination with quantum mechanics calculation and molecular dynamics simulation to more accurately describe the behavior of AB double-layer graphene under irradiation and electric field. The specific formula and algorithm are consistent, and specifically include the following steps: S10.1. Use quantum mechanics calculation methods to calculate the electronic structure and band structure of AB bilayer graphene. Use high-precision quantum mechanics calculation methods, such as density functional theory (DFT), to accurately calculate the electronic structure, band structure, and state density of graphene, taking into account the influence of long-range van der Waals interactions and external electric fields, and analyze the distribution and movement of electrons in graphene. For example, by calculating the band structure, the type and value of the band gap, as well as the regulation of the band gap by the external electric field, can be determined. At the same time, the wave function and orbital hybridization of electrons can be analyzed to understand the behavior of electrons under irradiation and electric fields. S10.2. Use molecular dynamics simulation methods to simulate the atomic motion and structural changes of AB bilayer graphene under irradiation and electric field. In molecular dynamics simulation, the effects of fast neutron irradiation and external electric field on carbon atoms are considered to simulate the motion trajectory, energy transfer and structural changes of atoms. Different force field models and simulation parameters can be used to accurately describe the mechanical behavior of graphene under irradiation and electric field. For example, through simulation, atomic displacement, interlayer spacing changes and surface ripple formation caused by irradiation can be observed; external electric field can cause changes in polarization and charge distribution of carbon atoms. At the same time, key parameters in the simulation process, such as temperature, pressure, energy, etc., are recorded for subsequent analysis. S10.3. Combine the results of quantum mechanics calculations and molecular dynamics simulations to conduct multi-scale analysis and research. Combine the electronic structure information obtained from quantum mechanics calculations with the atomic structure changes obtained from molecular dynamics simulations to conduct multi-scale analysis. For example, by analyzing the changes in the density of states of electrons under irradiation and electric fields, we can understand the excitation and transition processes of electrons. At the same time, combined with the changes in the atomic structure, we can analyze the interaction between electrons and atoms. In addition, we can study the combined effects of irradiation and electric fields on the electrical, mechanical, and optical properties of graphene, and explore its application potential in carbon-based devices. Through multi-scale simulations, we can have a more comprehensive understanding of the behavior of AB bilayer graphene under irradiation and electric fields, and provide theoretical support for the design and optimization of carbon-based devices.

[0023] Embodiment 5, Compared with Example 1, this embodiment is different in that, based on Example 1, the defects in AB double-layer graphene, such as vacancies and impurities, are explored to determine their effects on performance under irradiation and electric field. The specific formula and algorithm are consistent, and the following steps are specifically included: S11.1. Construct a defective AB double-layer graphene microstructure model, introduce defects of different types and concentrations into the graphene model, such as vacancy defects and impurity atoms, consider the influence of the position, type and concentration of defects on the graphene structure, and adjust the model parameters to accurately reflect the existence of defects. For example, a graphene model containing a single vacancy defect, multiple vacancy defects or impurity atoms replacing carbon atoms can be constructed. At the same time, analyze the influence of defects on the electronic structure and mechanical properties of graphene to provide a basis for subsequent simulation research; S11.2. Simulate irradiation and applied electric field to study the effect of defects on the microstructure of AB bilayer graphene. Simulate fast neutron irradiation and applied electric field on a graphene model with defects to observe the effect of defects on the graphene structure under irradiation and electric field. For example, defects may cause local atomic displacement and structural deformation, affecting the change of interlayer spacing and configuration. At the same time, analyze the effect of defects on the formation and development of surface ripples and the difference with defect-free graphene. Record the atomic motion trajectory and energy transfer process around the defects to gain a deeper understanding of the interaction between defects and irradiation and electric field. S11.3. Calculate the energy band structure of the AB bilayer graphene system with defects, analyze the effect of defects on the energy band structure, calculate the energy band structure of the graphene system with defects, and compare the difference with defect-free graphene. Defects may introduce new energy levels and state density distributions, and change the band gap type and band gap value. For example, vacancy defects may cause the band gap to increase or decrease, and impurity atoms may introduce impurity energy levels, affecting the transmission and optical properties of electrons. Analyze the effect of defects on the distribution of electrostatic potential and electron wave functions, and understand the role of defects on the movement and transition of electrons in graphene. S11.4. Calculate the elastic constants of defective systems and analyze the effect of defects on the Young's modulus of AB bilayer graphene. By calculating the elastic constants of defective graphene systems, evaluate the effect of defects on the Young's modulus. Defects may reduce the elastic modulus of graphene and affect its mechanical properties. Analyze the influence of different types and concentrations of defects on the elastic modulus, as well as the synergistic effect with irradiation and electric field. For example, under the action of irradiation and electric field, defects may lead to a further decrease in the elastic modulus, affecting the stability and reliability of carbon-based devices. S11.5. Use the RPA method to perform DFT calculations on the optical properties of defective AB bilayer graphene and analyze the effects of defects on the optical properties. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties of defective graphene systems and analyze the effects of defects on the complex dielectric function, light absorption coefficient, and refractive index. Defects may change the optical response of graphene and affect its application in optoelectronic devices. For example, vacancy defects may cause an increase or decrease in the light absorption coefficient, and impurity atoms may introduce new optical absorption peaks. At the same time, analyze the changes in optical properties under the combined effects of defects, irradiation, and electric fields to provide theoretical guidance for the design of carbon-based devices with specific optical properties.

[0024] Through the above embodiments, the effects of radiation damage on the carbon-based material AB double-layer graphene under fast neutron irradiation, external electric field, different radiation sources, temperature changes and defects can be comprehensively studied, and the effects of various factors on the microstructure, band structure, Young's elastic modulus and optical properties of AB double-layer graphene can be analyzed, so as to provide theoretical support for the design and optimization of carbon-based devices, and at the same time, provide a reference for radiation protection and material performance improvement.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for the irradiation damage of carbon-based material AB double-layer graphene, characterized in that: The specific steps include: S1, constructing a microstructure model, constructing an AB double-layer graphene microstructure model, wherein the AB double-layer graphene microstructure model is composed of 4×4 double-layer graphene super monomers, and the Z-direction height is set to 20Å, wherein the double-layer graphene super monomer has 64 atoms; S2. Fast neutron irradiation simulation. In molecular dynamics, the irradiation process is simulated by increasing the speed of a single C atom. The speed direction is along the negative direction of the Z axis. The irradiation process is simplified to carbon atoms (C) absorbing energy, thereby increasing the atomic kinetic energy and causing lattice disturbance. The fast neutron energy is set to 1MeV and the irradiation dose is 1×10 13 n / cm², the relaxation step size was set to 1 fs, and 10000 steps (10 ps) of relaxation were performed under NVE to reach equilibrium; The formula for calculating the energy (T) transferred by the incident neutron is: , ,in, is the incident neutron energy, T is the energy transferred by the incident neutron, r is the energy loss in the inelastic collision, and A is the atomic mass of the recoil atom; S3, applied electric field, applied electric field (−0.1 V / Å to −0.4 V / Å) to the initial structure, studied the effect of electric field on the microstructure, band structure, Young's elastic modulus and optical properties of the system, and selected the electric field strength of −0.2 V / Å for subsequent research; S4. Statistical microstructural parameters, including the coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF of AB bilayer graphene before and after irradiation, analyze the effects of fast neutron irradiation and applied electric field on the microstructure, and infer the relationship between the configuration change and surface ripple generation of AB bilayer graphene and the irradiation damage of carbon-based devices; S5. Calculate the energy band structure of the AB bilayer graphene system before and after irradiation, analyze the effects of fast neutron irradiation and applied electric field on the energy band structure, including the changes in band gap type, band gap value and electrostatic potential, and explore the effect of applied electric field on the accurate regulation of the band gap of AB bilayer graphene; S6. Calculate the elastic constants and Young's elastic modulus, and calculate the elastic constants (C 11 , C 12 , C 22 , C 66 ), the mechanical stability of the system is determined according to the Born-Huang criteria, and the effects of fast neutron irradiation and applied electric field on the Young's modulus of AB bilayer graphene, as well as the effects on phonon group velocity, thermal conductivity and carrier mobility are analyzed; Among them, the formula for calculating the Young's elastic modulus (Y) of the two-dimensional material hexagonal system AB double-layer graphene is: Among them, C 11、 C 12、 C 22 and C 66 The parameters can be read out through the calculated elasticity matrix; S7. Calculate the optical properties. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties. Calculate the complex dielectric function, light absorption coefficient and refractive index of the system. Analyze the effects of fast neutron irradiation and applied electric field on the optical properties of AB bilayer graphene, including the changes in the real and imaginary parts of the dielectric function, the light absorption coefficient and the parallel and perpendicular components of the refractive index. The formula for calculating the complex dielectric function is: in, and are the real and imaginary parts of the dielectric function, respectively, ω is the photon frequency; calculate The formula is: (ω)=1+ p calculate The formula is: The formula for light absorption coefficient is: in, is the speed of light in a vacuum; The formula for refractive index is: n(ω) in, and are the real and imaginary parts of the dielectric function, respectively.

2. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S1, when constructing the AB bilayer graphene microstructure model, the Perdew-Burke-Ernzerhof approximation in the generalized gradient approximation of the projector augmentedwave in the VASP tool is used to calculate the electronic structure, optical properties and mechanical properties of the AB bilayer graphene. At the same time, optB88 vdW is used as a function to help consider long-range van der Waals interactions.

3. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S1, a 5×5×1 k-point grid centered on Γ was used in the calculation of structural optimization and mechanical properties. A 7×1×1 k-point grid with higher accuracy was used for both self-consistent and non-self-consistent calculations except for optical properties. When calculating optical properties, a 13×13×1 K-point grid centered on Γ was used for Brillouin zone sampling. The plane wave cutoff energy was set to 500 eV, and the convergence values ​​of the total electron energy and ion force were 1.0×10 -6 eV, 0.01eV / Å, ISMEAR=0.

4. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S5, a 20 k-point grid is used for the Brillouin zone along the path G - M - K - G when performing the band calculation.

5. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S4, when analyzing the effects of fast neutron irradiation and external electric field on the microstructure of AB bilayer graphene, the greater the fast neutron irradiation energy, the greater the impact on the microstructure. The external electric field has limited effect on the microstructure of the system, but fast neutron irradiation under an external electric field will lead to further changes in the average interlayer spacing and configuration of the system. The superposition of electric field and irradiation will lead to further reduction of the symmetry and periodicity of the system.

6. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S5, when analyzing the effects of fast neutron irradiation and external electric field on the band structure of AB bilayer graphene, it is found that fast neutron irradiation has limited effect on the band structure of AB bilayer graphene, and the band gap will open slightly after irradiation. The effect of fast neutron irradiation on the band gap value under an external electric field is very different from the effect on the microstructure. Further changes in the average interlayer spacing of the system under external electric field irradiation lead to the diversity of the system configuration, and the diversity of configuration ultimately leads to the diversity of the system band structure. Under the condition of a certain fast neutron dose, the type and size of the band gap of the system after external electric field irradiation depends on the intensity of the applied electric field and the size of the irradiation energy. In a fast neutron irradiation environment, the accurate regulation of the band gap of AB bilayer graphene by the external electric field will fail.

7. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S6, when analyzing the effects of fast neutron irradiation and applied electric field on the Young's modulus of AB bilayer graphene, the Y of AB bilayer graphene decreases monotonically with the increase of fast neutron irradiation energy. Fast neutron irradiation has a certain negative impact on the phonon group velocity, thermal conductivity and carrier mobility of AB bilayer graphene. Fast neutron irradiation under an applied electric field will cause the Y of AB bilayer graphene to decrease faster than fast neutron irradiation alone. Fast neutron irradiation under an applied electric field will have a greater negative impact on the phonon group velocity, thermal conductivity and carrier mobility of AB bilayer graphene than fast neutron irradiation alone.

8. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: In step S7, when analyzing the effects of fast neutron irradiation and external electric field on the optical properties of AB bilayer graphene, the changes in the optical properties of the AB bilayer graphene system caused by fast neutron irradiation are mainly due to the changes in the system configuration induced by fast neutron irradiation. Fast neutron irradiation under an external electric field will also cause changes in the optical properties of the system. This is because, on the one hand, it is due to the effect of the external electric field on the system, and on the other hand, fast neutron irradiation under an external electric field will induce changes in the system configuration, which in turn lead to changes in the optical properties of the system.

9. The method for treating irradiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: The changes in the configuration of AB bilayer graphene induced by fast neutron irradiation and the appearance of induced surface ripples are the two main reasons for the changes in various properties of the system. The appearance of surface ripples and the changes in configuration may be two important reasons for the performance degradation and damage of carbon-based devices. The uncertainty of the type and size of the band gap of AB bilayer graphene under fast neutron irradiation with an external electric field may be one of the reasons for the performance degradation and permanent damage of carbon-based devices in practical applications. In addition, regardless of whether an external electric field is applied, the effects of fast neutron irradiation with an energy difference of one order of magnitude (1×10¹³n / cm² dose) on various properties of AB bilayer graphene are significantly different.

10. The method for treating radiation damage of carbon-based material AB double-layer graphene according to claim 1, characterized in that: The following different methods are also included, specifically including the following steps: S8. Introduce other types of radiation sources, such as protons, alpha particles and heavy ions, to study their effects on the radiation damage of AB bilayer graphene, specifically including the following steps: S8.

1. Construct a microstructure model of AB bilayer graphene under different irradiation sources. For each irradiation source, consider its interaction characteristics with carbon atoms and adjust the model parameters to more accurately reflect the initial state under different irradiation conditions. For example, for proton irradiation, it may be necessary to consider the impact effect of the smaller mass and higher velocity of protons on the graphene structure; for heavy ion irradiation, it is necessary to consider the strong local disturbance caused by the high energy and larger mass of heavy ions; S8.

2. In molecular dynamics, simulate the irradiation process of different irradiation sources, set the corresponding irradiation energy and dose, and determine the reasonable irradiation energy range and dose level according to the physical properties of different irradiation sources. For example, the irradiation energy of protons can be gradually increased from a low value to study its effect on graphene at different energies. The energy of alpha particles is usually high, and the dose needs to be adjusted appropriately to avoid excessive damage to the structure. At the same time, record the motion trajectory and energy transfer process of carbon atoms under different irradiation sources. S8.

3. Statistical analysis of the microstructure parameters of AB bilayer graphene before and after irradiation, and analysis of the effects of different irradiation sources on the microstructure. In addition to the original parameters such as coordination number, interlayer spacing range, interlayer spacing fluctuation, BAD and PDF, the carbon atom displacement distribution and chemical bond changes caused by different irradiation sources can be further analyzed. For example, for heavy ion irradiation, more obvious local structural deformation and chemical bond breakage may be observed; for α-particle irradiation, structural damage in a specific direction may occur; S8.

4. Calculate the band structure of the AB bilayer graphene system before and after irradiation, analyze the effects of different irradiation sources on the band structure, and compare the band gap type, band gap value changes, and electrostatic potential distribution under different irradiation sources. It may be found that the band structure changes caused by different irradiation sources have unique rules. For example, proton irradiation may cause a small band gap change, but has a specific effect on the shape and distribution of the energy band; heavy ion irradiation may cause a large band gap change and disorder of the band structure. S8.

5. Calculate the elastic constants of the system before and after irradiation, analyze the effect of different irradiation sources on the Young's modulus of AB bilayer graphene, and evaluate the change of Young's modulus by calculating parameters such as C11, C12, C22, and C66 under different irradiation sources. Different irradiation sources may have different effects on the elastic modulus. For example, α-particle irradiation may significantly reduce the elastic modulus, while proton irradiation has a relatively small effect. At the same time, analyze the effect on phonon group velocity, thermal conductivity, and carrier mobility, and explore the change rules of these properties under different irradiation sources. S8.

6. Use the RPA method to perform DFT calculations on the optical properties, analyze the effects of different irradiation sources on the optical properties of AB bilayer graphene, calculate the complex dielectric function, light absorption coefficient and refractive index of the system under different irradiation sources, and study the differences with fast neutron irradiation. For example, heavy ion irradiation may lead to a significant increase in the light absorption coefficient, while proton irradiation may have a more obvious effect on the refractive index. At the same time, analyze the reasons for the changes in optical properties under different irradiation sources and link them to changes in microstructure and band structure. S9. Considering the effects of fast neutron irradiation and external electric field on AB double-layer graphene under different temperature conditions, the following steps are specifically included: S9.

1. Construct a microstructure model of AB bilayer graphene at different temperatures, taking into account the thermal expansion effect of temperature on graphene and adjusting the atomic spacing and lattice parameters of the model. For example, at higher temperatures, the atomic vibration of graphene intensifies and the interlayer spacing may increase slightly. At the same time, considering the effect of temperature on the chemical bonds between carbon atoms, the bond length and bond angle may change. S9.

2. Simulate fast neutron irradiation and applied electric field, record the changes of the system at different temperatures, simulate fast neutron irradiation and applied electric field at different temperatures, observe the influence of temperature on the system under irradiation and electric field, record the movement trajectory of carbon atoms, energy transfer and electric field distribution, and analyze the interaction between temperature, irradiation and electric field. For example, at higher temperatures, fast neutron irradiation may lead to more violent atomic movement and structural damage; the effect of applied electric field may be affected by temperature, resulting in changes in the electrical properties of the system; S9.

3. Analyze the effects of different temperatures on the microstructure, band structure, Young's modulus and optical properties of AB bilayer graphene. For the microstructure, analyze the changes in interlayer spacing, atomic displacement and configuration caused by temperature. For the band structure, study the effects of temperature on the type and value of band gaps, as well as the changing laws of band structure under the combined effects of temperature, irradiation and electric field. For Young's modulus, evaluate the degree of influence of temperature on the modulus, as well as the synergistic effects with irradiation and electric field. For optical properties, calculate the complex dielectric function, light absorption coefficient and refractive index at different temperatures, and analyze the mechanism of the influence of temperature on optical properties. For example, higher temperatures may lead to an increase in the light absorption coefficient, and the change in refractive index may also be related to temperature. At the same time, consider the combined effects of temperature, irradiation and electric field on the performance of carbon-based devices to provide a more comprehensive theoretical basis for practical applications. S10. Combining quantum mechanical calculations and molecular dynamics simulations, a multi-scale simulation study was conducted to more accurately describe the behavior of AB bilayer graphene under irradiation and electric field, including the following steps: S10.

1. Use quantum mechanics calculation methods to calculate the electronic structure and band structure of AB bilayer graphene. Use high-precision quantum mechanics calculation methods, such as density functional theory (DFT), to accurately calculate the electronic structure, band structure, and state density of graphene, taking into account the influence of long-range van der Waals interactions and external electric fields, and analyze the distribution and movement of electrons in graphene. For example, by calculating the band structure, the type and value of the band gap, as well as the regulation of the band gap by the external electric field, can be determined. At the same time, the wave function and orbital hybridization of electrons can be analyzed to understand the behavior of electrons under irradiation and electric fields. S10.

2. Use molecular dynamics simulation methods to simulate the atomic motion and structural changes of AB bilayer graphene under irradiation and electric field. In molecular dynamics simulation, the effects of fast neutron irradiation and external electric field on carbon atoms are considered to simulate the motion trajectory, energy transfer and structural changes of atoms. Different force field models and simulation parameters can be used to accurately describe the mechanical behavior of graphene under irradiation and electric field. For example, through simulation, atomic displacement, interlayer spacing changes and surface ripple formation caused by irradiation can be observed; external electric field can cause changes in polarization and charge distribution of carbon atoms. At the same time, key parameters in the simulation process, such as temperature, pressure, energy, etc., are recorded for subsequent analysis. S10.

3. Combine the results of quantum mechanics calculations and molecular dynamics simulations to conduct multi-scale analysis and research. Combine the electronic structure information obtained from quantum mechanics calculations with the atomic structure changes obtained from molecular dynamics simulations to conduct multi-scale analysis. For example, by analyzing the changes in the density of states of electrons under irradiation and electric fields, we can understand the excitation and transition processes of electrons. At the same time, combined with the changes in atomic structure, we can analyze the interaction between electrons and atoms. In addition, we can study the combined effects of irradiation and electric fields on the electrical, mechanical and optical properties of graphene and explore its application potential in carbon-based devices. Through multi-scale simulations, we can more comprehensively understand the behavior of AB bilayer graphene under irradiation and electric fields, and provide theoretical support for the design and optimization of carbon-based devices. S11. Explore the effects of defects in AB bilayer graphene, such as vacancies and impurities, on its performance under irradiation and electric field, including the following steps: S11.

1. Construct a defective AB double-layer graphene microstructure model, introduce defects of different types and concentrations into the graphene model, such as vacancy defects and impurity atoms, consider the influence of the position, type and concentration of defects on the graphene structure, and adjust the model parameters to accurately reflect the existence of defects. For example, a graphene model containing a single vacancy defect, multiple vacancy defects or impurity atoms replacing carbon atoms can be constructed. At the same time, analyze the influence of defects on the electronic structure and mechanical properties of graphene to provide a basis for subsequent simulation research; S11.

2. Simulate irradiation and applied electric field to study the effect of defects on the microstructure of AB bilayer graphene. Simulate fast neutron irradiation and applied electric field on a graphene model with defects to observe the effect of defects on the graphene structure under irradiation and electric field. For example, defects may cause local atomic displacement and structural deformation, affecting the change of interlayer spacing and configuration. At the same time, analyze the effect of defects on the formation and development of surface ripples and the difference with defect-free graphene. Record the atomic motion trajectory and energy transfer process around the defects to gain a deeper understanding of the interaction between defects and irradiation and electric field. S11.

3. Calculate the energy band structure of the AB bilayer graphene system with defects, analyze the effect of defects on the energy band structure, calculate the energy band structure of the graphene system with defects, and compare the difference with defect-free graphene. Defects may introduce new energy levels and state density distributions, and change the band gap type and band gap value. For example, vacancy defects may cause the band gap to increase or decrease, and impurity atoms may introduce impurity energy levels, affecting the transmission and optical properties of electrons. Analyze the effect of defects on the distribution of electrostatic potential and electron wave functions, and understand the role of defects on the movement and transition of electrons in graphene. S11.

4. Calculate the elastic constants of defective systems and analyze the effect of defects on the Young's modulus of AB bilayer graphene. By calculating the elastic constants of defective graphene systems, evaluate the effect of defects on the Young's modulus. Defects may reduce the elastic modulus of graphene and affect its mechanical properties. Analyze the influence of different types and concentrations of defects on the elastic modulus, as well as the synergistic effect with irradiation and electric field. For example, under the action of irradiation and electric field, defects may lead to a further decrease in the elastic modulus, affecting the stability and reliability of carbon-based devices. S11.

5. Use the RPA method to perform DFT calculations on the optical properties of defective AB bilayer graphene and analyze the effects of defects on the optical properties. Use the random phase approximation (RPA) method to perform DFT calculations on the optical properties of defective graphene systems and analyze the effects of defects on the complex dielectric function, light absorption coefficient, and refractive index. Defects may change the optical response of graphene and affect its application in optoelectronic devices. For example, vacancy defects may cause an increase or decrease in the light absorption coefficient, and impurity atoms may introduce new optical absorption peaks. At the same time, analyze the changes in optical properties under the combined effects of defects, irradiation, and electric fields to provide theoretical guidance for the design of carbon-based devices with specific optical properties.

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