Mxene Synthesis: HCl‐Based Hydrothermal Etching Strategy toward Fluoride‐Free MXenes (Adv. Mater. 27/2021)

New synthesis strategies of fluoride-free MXenes beyond Ti3C2Tx are imperative to extend 2D MXenes. In article number 2101015, Pulickel M. Ajayan, Li Song, and co-workers simulate the feasibility of etching various MAX materials in HCl solution influenced by temperature and pressure. Fluoride-free Mo2CTx MXene is then obtained with high quality and efficiency via a controllable HCl hydrothermal etching method, which exhibits a modulated energy-storage mechanism.