Adsorption of Ca on borophene for potential anode for Ca-ion batteries.

Context: Two-dimensional borophene can be used in rechargeable batteries due to its high specific surface area. In this paper, the performance of borophene as an anode material for calcium ion batteries is predicted based on density functional theory calculations. The calculation results show that P doping enhances the calcium storage properties of borophene. The maximum adsorption number of calcium atoms in the P-doped system is 7, with a theoretical capacity of 964 mAh/g. DOS analysis showed that borophene exhibited metallic properties after adsorbing calcium atoms, which improved the electrical conductivity of the electrode material. Calculation of the diffusion energy barrier shows that strain has an effect on calcium diffusion in monolayer borophene, and compressive strain promotes calcium diffusion through borophene. The findings suggest that borophene may be a promising electrode material for calcium-ion batteries.

Methods: In this paper, the intrinsic model and doping model of borophene are constructed by Material Studio 8.0, and the first-principles calculation is carried out by CASTEP module.