Highly stable few-layer V2CTx MXene/Carbon nanotube structure with restrained restacking for lithium ion storage

V2CTx MXene has shown potential as an electrode material for lithium-ion batteries (LIBs) due to its high theoretical capacity. However, most reports on V2CTx are confined to multilayer structures in LIBs, and V2CTx nanosheets have a serious restacking problem, which results in their low cyclic stability. Herein, we report the synthesis of few-layer V2CTx/carbon nanotubes (CNTs) composite by tetramethylammonium hydroxide (TMAOH) delamination and electrostatic flocculation of NH4+ ions. Few-layer V2CTx nanosheets with crimped structure can effectively restrain restacking and guarantee full utilization of active surface area. Moreover, with the introduction of CNTs, a developed electrical conductivity network was formed, and CNTs provided structural support for the sheets further restraining their restacking, and ensuring their stable structure during the charge and discharge process even at high rates. This made the few-layer V2CTx/CNT to exhibit a high specific capacitance of 621 mAh/g after 100 cycles at 0.1 A/g, and outstanding rate performance of 290 mAh/g at 5 A/g. Furthermore, the few-layer V2CTx/CNT electrode showed excellent cycling stability with 82.1 % capacitance retention after 2000 cycles at 5 A/g. This shows it has significant potential for lithium-ion batteries applications.