Very High-Capacity Li/Na-Ion battery anodes Enabled by Blue phosphorene and boron phosphide vdW heterostructure

Abstract

The fascinating features of van der Waals heterostructure (vdWH) based electrodes and their potential to overcome the limiting properties of single-material systems have sparked a great deal of scientific attention. In this study, we investigate the potential of a blue phosphorene/boron phosphide (Blue-P/BP) vdWH as an anode material for both lithium-ion (Li-ion) and sodium-ion (Na-ion) batteries using first-principles calculations. We suggest that this vdWH could act as an effective anode material for metal-ion batteries, due to their high theoretical capacity and strong binding strength. Intriguingly, the theoretical specific capacity exhibits remarkable values, notably reaching 4510 mAhg−1 for Li and 3849 mAhg−1 for Na, which surpasses all capacities reported in the existing literature. Additionally, electronic structure calculations reveal a significant charge transfer that enhances the metallic characteristics, thereby increasing electrical conductivity. As we delve deeper into the electronic structure and calculate diffusion barriers and pathways, we observe that ionic diffusion (∼0.12/0.11 eV) is notably rapid compared to graphitic anodes (∼0.2 eV). We also found that intercalating Li/Na atoms in the Blue-P/BP vdWH results in low operating potentials of 0.38 V for Li and 0.34 V for Na. This research highlights the substantial enhancement of electrochemical performance of Blue-P/BP vdWH and holds great promise as high-power-density anode materials for Li/Na-ion batteries, facilitating rapid charge and discharge rates.