An MXene/CNTs@P nanohybrid with stable Ti-O-P bonds for enhanced lithium ion storage

Two-dimensional transition metal carbides (MXenes) have a unique structure, excellent electronic conductivity and a low Li⁺ diffusion barrier, and show potential for application in energy storage. Especially, MXenes can act as a conductive matrix to achieve excellent lithium storage performance. Herein, a Ti₃C₂T_x MXene/carbon nanotubes@red phosphorus (Ti₃C₂T_x/CNTs@P) nanohybrid with stable Ti-O-P bonds is fabricated. The CNTs are introduced into Ti₃C₂T_x to construct a conductive network, and then the Ti₃C₂T_x/CNTs are combined with P by a ball-milling method. In this process, the surface oxygen-containing functional groups of Ti₃C₂T_x interact with P, forming Ti-O-P bonds. Owing to the large capacity contribution of P, the conductive network and buffering role of Ti₃C₂T_x/CNTs, and the effect of the Ti-O-P bond, the Ti₃C₂T_x/CNTs@P nanohybrid exhibits a superior reversible capacity of 2598 mA h g^-1 at 0.05C (1C = 2600 mA g^-1, based on the active material P), excellent cycling stability (2078 mA h g^-1 after 500 cycles) and superior rate capability (454 mA h g^-1 at 30C). These results demonstrate that the Ti₃C₂T_x/CNTs@P nanohybrid offers fascinating potential for high-performance lithium-ion batteries.