Transition metal dichalcogenide-decorated MXenes: promising hybrid electrodes for energy storage and conversion applications

Various two-dimensional (2D) materials have demonstrated unique structure-dependent characteristics that are conducive to energy-harvesting applications. Among them, the family of layered MXenes has found a wide range of applications in batteries, supercapacitors, photo- and electrocatalysis, water purification, biosensors, electromagnetic interference shielding, structural composites, etc., owing to their well-defined structure, large surface area, large interlayer distance, and excellent thermal and electrical conductivity. However, layer restacking due to hydrogen bonding or van der Waals forces between the layers considerably impedes the utility of MXenes. To tackle the restacking issues, transition metal dichalcogenides (TMDs) such as MoS2, WS2, and MoSe2 nanosheets have been uniformly dispersed on the surface of MXenes, which not only mitigates the restacking of the MXenes but also improves the electrochemical performance due to the synergistic interaction between MXenes and TMDs. This review describes recent advances in the synthesis of MXene/TMD heterostructures and the nature of the synergistic interactions between TMDs and MXenes in energy-related applications. We further highlight future research directions for MXene/TMD-based materials for energy storage applications.