Molten Salt Derived Nb₂CT_<i>x</i> MXene Anode for Li‐ion Batteries

Abstract 2D MXenes, are receiving increasing attention thanks to their outstanding performance for electrochemical energy‐storage applications. So far, Ti 3 C 2 is the most studied MXene, while less effort is dedicated to investigating many other MXenes. In this paper, we report the preparation of Nb 2 CT x MXene by Lewis acidic etching in molten salts. The achieved Nb 2 CT x MXene is able to deliver a maximum lithium storage capacity up to 330 mAh g −1 at 0.05 A g −1 , outperforming the maximum capacity (205 mAh g −1 ) achieved by molten salt derived Ti 3 C 2 T x MXene. The high‐rate performance is also obtained with a capacity of 80 mAh g −1 at 10 A g −1 (100 C). This work highlights the promising potential of Nb‐based MXenes to be explored as high‐rate lithium storage electrodes.