Li-ion storage properties of two-dimensional titanium-carbide synthesized via fast one-pot method in air atmosphere.

Abstract

Structural bidimensional transition-metal carbides and/or nitrides (MXenes) have drawn the attention of the material science research community thanks to their unique physical-chemical properties. However, a facile and cost-effective synthesis of MXenes has not yet been reported. Here, using elemental precursors, we report a method for MXene synthesis via titanium aluminium carbide formation and subsequent in situ etching in one molten salt pot. The molten salts act as the reaction medium and prevent the oxidation of the reactants during the high-temperature synthesis process, thus enabling the synthesis of MXenes in an air environment without using inert gas protection. Cl-terminated Ti₃C₂T_x and Ti₂CT_x MXenes are prepared using this one-pot synthetic method, where the in situ etching step at 700 °C requires only approximately 10 mins. Furthermore, when used as an active material for nonaqueous Li-ion storage in a half-cell configuration, the obtained Ti₂CT_x MXene exhibits lithiation capacity values of approximately 280 mAh g^-1 and 160 mAh g^-1 at specific currents of 0.1 A g^-1 and 2 A g^-1, respectively.