Mn2+ Intercalated V2C MXene for Enhanced Sodium Ion Battery

Abstract

Mn2+ intercalation strategy to optimize the sodium storage performance of V2C MXene was studied. The intercalated Mn2+ not only enlarged the interlayer spacing of V2C MXene but also formed a V-O-Mn covalent bond, which was beneficial to stabilize the structure of V2C and inhibit the structural collapse caused by volume change during Na+ decalation or intercalation. As a result, the intercalated V2C MXene (V2C@Mn) electrode showed a high specific capacity of 425 mAh•g-1 at the current density of 0.05 A•g-1, and 70% retention after 1200 cycles. This result clearly suggests that cations intercalated MXene has a great prospect in Na+ storage.