Ion-intercalation Architecture for Robust Functionalization of Two-Dimensional MXenes

Due to the unique two-dimensional (2D) structures and the derived properties, MXenes have attracted significant scientific interest and been thereof developed rapidly since their discovery in 2011. The sub-nanometer interlayer spacing between 2D MXene sheets can accommodate a variety of intercalation agents toward optimized physical and chemical properties. Among these intercalation agents, ion intercalation has special advantages due to its charge and intrinsic small size. Ion intercalation plays a crucial role in lattice modification, surface state regulation, and in turn optimization of electronic/chemical properties for MXene materials. Herein, in order to guide the further study of ion intercalated into MXenes, we present a state-of-the-art overview of ion interaction events into MXenes, ranging from the interactions between MXenes and ions, and advanced characterization techniques, to the influencing factors, mechanism and functionalization-oriented roles of ion intercalation.