Stone-Wales type defect induced performance enhancement in BC₃ monolayer for Lithium-ion battery anode applications

Based on first-principles density functional theory (DFT) simulations, we systematically explored the possibility of pristine and defective two-dimensional boron carbide (BC₃) monolayer for designing high-performance Li-ion battery (LIB) anodes. Our calculations show that the BC₃ monolayer possesses significant structural and electronic stability and also noticed that after adsorbing Li atom, the semiconducting characteristic of both pristine and defective BC₃ monolayer is transformed into a metallic state, becoming an electrical conductor, which provided enhanced conductivity for LIB application. Our results reveal the Li adsorption in these structures are exothermic and the Stone-Wales type defect filled BC₃ shows a higher theoretical specific capacity of 1287 mAhg^-1 for Li atoms compared to pristine BC₃ (1144 mAhg^-1) and conventional graphite anode (372 mAhg^-1). We also found that both the pristine and defect filled BC₃ possess fast Li mobility with a low diffusion barrier (~ 0.33 eV) as well as a low average open-circuit voltage (< 0.48 V). Because of these excellent properties, our work predicts that the experimentally synthesized BC₃ monolayer, especially the one with Stone-Wales defect can be a promising anode material for the development of future LIBs.