Towards high-performance electrocatalysts and photocatalysts: Design and construction of MXenes-based nanocomposites for water splitting

Abstract

• A comprehensive report on the photocatalytic and electrocatalytic water splitting properties of MXenes are expressed. • A future research direction of MXenes-based materials is prospected. • This review offers a comprehension for optimization of MXenes-based catalysts. • The photocatalytic and electrocatalytic mechanism of MXenes are summarized. Photocatalytic and electrocatalytic water splitting are now playing a key role in solving the energy and environment problems. Two-dimensional (2D) transition metal carbides/carbonitrides/nitrides (MXenes) are considered as a promising 2D nanomaterials in the photocatalytic and electrocatalytic water splitting application space due to the excellent hydrophilicity, metal-like conductivity, high surface area/volume ratio and rich surface chemistry. However, several challenges, including poor environmental ability and limited intrinsic catalytic activities, should be overcome before practical applications. In the review, the recent advances on the synthesis, technical challenges as well as catalytic performance improvement of MXenes are comprehensively summarized. The catalytic mechanism of MXenes and in-depth discussion on the photocatalytic and electrocatalytic water splitting properties of MXenes are systematically summarized. Finally, an insight into the future research directions and further developments of MXenes-based materials is prospected in order to accelerate their extensive application in the fields of electrocatalysts and photocatalysts. This review can provide important comprehension for construction and optimization of high-performance MXenes-based electrocatalysts and photocatalysts.