Synthesis of MXene/carbon composites via controlled etching of Ti3SiC2 in the gaseous etchant CCl4

Abstract

The study investigates the structural evolution of Ti₃SiC₂ using the gaseous etchant CCl₄, emphasizing its ability to selectively etch Si and Ti atoms to form an MXene (Ti₃C₂Cl₂)/carbon composite and carbide-derived carbon (CDC). Under specific conditions, a complete conversion to the MXene is accomplished at a Ti₃SiC₂ : CCl₄ molar ratio of 1 : 3.5, whereas higher CCl₄ concentrations lead to further oxidation of Ti₃C₂Cl₂ and formation of lamella CDC. This method presents an alternative chemical etching route to synthesize MXenes. Importantly, the production of CDC using CCl₄ as an etchant could obtain carbon/MXene hybrids with significant implications for promising energy storage applications.