Synthesis of high-quality ultrathin titanium carbide nanosheets and films through immiscibility approach

Two-dimensional (2D) transition metal carbides (TMCs) have been explored widely in energy storage and catalysis fields. However, it is challenging to fabricate high-quality 2D titanium carbide (TiCx) nanosheets with surface functional groups free, uniform size and thickness, and defects free. Here, we demonstrate a simple method to fabricate high-quality ultrathin TiCx nanosheets through an immiscibility approach by using chemical vapor deposition (CVD). Ultrathin Ti film (100 nm) was deposited on Cu foil as the substrate which makes Ti atoms immiscible on Cu foil. Ti atoms were transferred to the Cu substrate surface and reacted with CH4 to form ultrathin TiCx at high temperatures. The size (600 nm) and thickness (4 nm) of the obtained TiCx nanosheets are uniform. Additionally, ultrathin TiCx films werer obtained. This work provides a novel method to produce high-quality TMCs nanosheets and films in a simple and efficient way.