Novel two dimensional B2C3 monolayer as a high theoretical capacity anode material for Li or Na ion batteries

In this study, we utilized first-principles calculations to design a novel class of two-dimensional (2D) polycyclic materials composed of carbon and boron atoms, termed k-B₂C₃, which hold significant promise as high-capacity, fast-diffusing anode materials for Li/Na-ion batteries. We investigated the thermodynamic stability, mechanical properties, electronic structure, and energy storage characteristics of k-B₂C₃. The results reveal that k-B₂C₃ exhibits a density of states at the Fermi level of 0.18 states/eV, a Young's modulus of [Formula: see text], and a Poisson's ratio of 0.43, indicating excellent metallic conductivity and mechanical ductility, which are crucial for stability during charge/discharge cycles. Furthermore, the Li/Na diffusion barriers for k-B₂C₃ are 0.55 eV and 0.17 eV, respectively, which are vital for efficient charge/discharge processes. Most notably, k-B₂C₃ demonstrates a high theoretical storage capacity of 930 mAhg^-1 for both Li and Na, coupled with low open-circuit voltages (1.30-0.54 V for Li and 1.17-0.34 V for Na). These findings suggest that 2D k-B₂C₃ is a promising candidate for use as an anode material in Li/Na-ion batteries and provides valuable insights for the development of advanced 2D electrode materials.