二维半导体R57-BN作为钠离子电池阳极材料的理论研究OA北大核心CSTPCD

As promising alternatives to lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)have garnered significant interest owing to the abundant resources,low cost,and similar storage mechanism with LIBs.However,the lack of suitable anode materials is a major bottleneck of SIBs.Two-dimensional(2D)materials are promising anode materials for batteries due to their large surface area and short diffusion paths.In this paper,a pentagonal and heptagonal 2D semiconductor structure R57-BN composed of B and N atom was predicted,and the electrochemical properties of R57-BN as anode material of SIBs were studied based on first-principles calculations.2D R57-BN shows great stability in dynamic and thermodynamic aspects.The computation results reveal that Na atom can be adsorbed on R57-BN without clustering,and the adsorbed energy of Na-ion on the R57-BN is 1.55 eV.Even at low intercalated Na concentration,the Na adsorbed R57-BN system demonstrates metallic characteristics,showing good electronic conductivity.The diffusion barrier of Na diffusion on the surface of R57-BN is as low as 0.55 eV.Meanwhile,R57-BN has high specific capacity(662.40 mA·h/g)and suitable average open circuit voltage(VOC,0.50 V).Based on the above results,R57-BN can serve as a potential anode material for SIBs.The present research can provide a good theoretical basis and thus conduce to guiding the developing of good Na storage materials,and also supply strong background for experimental researches.