High-Temperature Behavior and Surface Chemistry of Carbide MXenes Studied by Thermal Analysis

Two-dimensional (2D) transition-metal carbides and nitrides (MXenes) have attracted significant attention due to their electronic, electrochemical, chemical, and optical properties. About 30 different MXenes have been synthesized, with several additional varieties predicted computationally, rendering them among the most diverse, tunable, and fastest growing families of 2D materials. The effect of post-treatment was analyzed by comparing multilayer (ML) MXene powders and free-standing films after delamination of ML MXene. In-depth understanding of the thermal analysis data and effects of the sample history on their thermal stability can better guide the tuning of MXene properties via thermal treatment under specific conditions to meet application requirements. The surface chemistry and texture control the hydrophilicity of MXenes, which is of great importance in applications where wettability/impermeability plays a major role. Thermal treatment of MXenes may be a viable option.