Two-Dimensional MXene with Controlled Interlayer Spacing for Electrochemical Energy Storage.

In this issue of ACS Nano, Luo et al. report the preparation of pillared two-dimensional (2D) Ti3C2 MXenes with controllable interlayer spacings between 1 and 2.708 nm. These materials were further intercalated by ion exchange with Sn(+IV) ions. The results show improved electrochemical performance due to improved ion accessibility into the 2D structure as well as the confinement effect, which limits volume expansion during the Li-alloying reaction. Beyond this specific example, the demonstration that the interlayer spacings of MXenes can be fine-tuned by creating pillared structures based on the spontaneous intercalation of surfactants opens new perspectives in the field of electrochemical energy storage.