Since the discovery of graphene, the quest for two-dimensional (2D) materials has intensified greatly
Transparent Conductive Two-Dimensional Titanium Carbide Epitaxial Thin Films
Since the discovery of graphene, the quest for two-dimensional (2D) materials has intensified greatly. Recently, a new family of 2D transition metal carbides and carbonitrides (MXenes) was discovered that is both conducting and hydrophilic, an uncommon combination. MXenes were produced as powders, flakes and colloidal solutions. Herein, we report on the fabrication of ~ 1x1 cm2 Ti3C2 films by selective etching of Al, from sputter-deposited epitaxial Ti3AlC2 films, in aqueous HF or NH4HF2. Films that were about 19 nm thick, etched with NH4HF2, transmit ~ 90% of the light in the visible-to-infrared range and exhibit metallic conductivity down to ~100 K. Below 100 K, the films’ resistivity increases with decreasing temperature and they exhibit negative magnetoresistance; both observations consistent with a weak localization phenomenon characteristic of many 2D defective solids. This advance opens the door for the use of MXenes in electronic, photonic and sensing applications.