Vertically aligned MoS2 nanosheets on monodisperse MXene as electrolyte-philic cathodes for zinc ion batteries with enhanced capacity.

Abstract

Zinc ion batteries (ZIBs) have attracted extensive attention for their high safety and environmentally friendly nature, and considerable theoretical capacities. Due to its unique two-dimensional layered structure and high theoretical specific capacities, molybdenum disulfide (MoS2) presents as a promising cathode material for ZIBs. Nevertheless, the low electrical conductivity and poor hydrophilicity of MoS2 limits its wide application in ZIBs. In this work, MoS2/Ti3C2Tx composites are effectively constructed using a one-step hydrothermal method, where two-dimensional MoS2 nanosheets are vertically grown on monodisperse Ti3C2Tx MXene layers. Contributing to the high ionic conductivity and good hydrophilicity of Ti3C2Tx, MoS2/Ti3C2Tx composites possess improved electrolyte-philic and conductive properties, leading to a reduced volume expansion effect of MoS2 and accelerated Zn2+ reaction kinetics. As a result, MoS2/Ti3C2Tx composites exhibit high voltage (1.6 V) and excellent discharge specific capacity of 277.8 mA h g-1 at 0.1 A g-1, as well as cycle stability as cathode materials for ZIBs. This work provides an effective strategy for developing cathode materials with high specific capacity and stable structure.