Rational Design of Two-Dimensional Porous Boron Phosphide as Efficient Cathode Material for Li and Na Ion Batteries: A First-Principles Study

The search for an efficient electrode material based on 2D materials for Li/Na-ion rechargable batteries is an emerging field of research in the recent times. By employing density functional theory (DFT) based calculations, we herein proposed a porous boron phosphide (p-BP) monolayer having superior electronic conductivity and enough thermodynamic stability as an excellent cathode material for Li/Na-ion batteries. We have analyzed the structure, stability, electronic structure of p-BP monolayer and addressed the adsorption of Li/Na atoms over the monolayer followed by the charge transfer and the chemical interaction between the alkali metal atom and the p-BP monolayer. The calculated diffusion energy barriers, are within the range of 0.031 to 0.495 eV. We have also measured the open circuit voltages of the studied systems that vary from 1.92 to 5.48 V, which supports the plausibility of an efficient cathode material. Finally, the Li storage capacity is found to be in between 689.4 and 931.96 mAh/g, while that of Na is in between 1378.8 to 1659.66 mAh/g. All these calculated results ensure that the p-BP monolayer is a promising new age cathode material for Li/Na-ion batteries.