Defect-independent migration of Li on C3B for Li-ion battery anode material

Abstract

Two dimensional C3B has attracted a lot of attentions due to its graphene-like structure. In this work, the potential of monolayer C3B as anode material of lithium-ion battery are systematically studied through first-principles calculations. The results show that pristine C3B has high stiffness (Young's modulus is 255.65 N/m), good binding strength of Li (−2.55~−2.66 eV), high capacity (1139.96 mA h/g) and good electronic (band gap is 0.64 eV) and ionic conductivity (diffusion barrier is 0.40 eV). It is also found that C3B-VC and C3B-VB has similar cohesive energy and formation energy. Interestingly, C3B shows good defect-independent Li migration capability. The migration barrier of Li on defect C3B was affected slightly by the vacancy, without the trap of Li. Moreover, the vacancy in C3B could improve conductivity and the adsorption ability of Li without the sacrifice of migration ability of Li. These interesting properties indicate that C3B has great potential for the application of anode material for LIBs.