Surface reformation of 2D MXene by in situ LaF3-decorated and enhancement of energy storage in lithium-ion batteries

Abstract

The two-dimensional transition metal carbides or nitrides Ti3C2Tx (MXene), has emerged as attractive electrode materials for lithium-ion batteries due to their metallic electrical conductivity and low ion diffusion barrier. However, the stabilities, electronic structures and other physicochemical properties of MXene are affected intensively by their surface species and structure. Here, a new architecture approach is demonstrated for reforming MXene through in situ-decorated LaF3, for boosting the performance of Li batteries in terms of capacity and rate ability. Ti3C2Tx@LaF3 can deliver an initial specific discharge capacity of 340 mAh/g under a current density of 50 mA/g and a reversible discharge capacity of 89.2 mAh/g at a current density of 1000 mA/g, which is significantly higher than that of pure Ti3C2Tx. Ti3C2Tx@LaF3 heterostructures enhance Li‐ion storage performance by shortens the charge transfer distance and improves the charge transfer rate during electrochemical reaction.