MXenes: Applications in electrocatalytic, photocatalytic hydrogen evolution reaction and CO2 reduction

[Display omitted] •The structure and properties of Mxenes were highlighted.•The synthesis approaches for producing MXenes with controlled quality were discussed.•The utilization of MXenes as catalysts for HER and CO2RR was critically reviewed.•Remaining challenges and future direction for the development of Mxenes for HER and CO2RR were provided. Two-dimensional MXenes have gained tremendous interest as frontier materials for a wide variety of applications and play a pivotal role in the development of future energy, electronic and optoelectronic devices as they exhibit high catalytic activity in diverse electrocatalytic and photocatalytic devices. The fabrication and application of MXenes as catalysts have become more progressive in recent years and more than 30 different varieties have been experimentally discovered and utilized. In this review, we rationally summarized and discussed the most recent advances in the synthesis and specific applications of MXenes as electrocatalysts and photocatalyst for hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2RR) including strategies for boosting their catalytic activity for target products. Finally, we highlight the lingering challenges and direction for the future development of MXenes as catalysts for HER and CO2RR.