TiS 2 nanoplates: A high-rate and stable electrode material for sodium ion batteries

Room temperature sodium-ion batteries are of great potential for large-scale energy storage applications because of the abundance and low cost of sodium resources. However, their future viability will largely hinge on the development of high-capacity and stable electrode materials. In this study, we report thin TiS2 nanoplates as a possible cathode material for sodium-ion batteries. These nanoplates possess nanoscale dimensions and large surface areas. Their interlayer galleries are open toward the edges, providing easy access to the large internal space. Electrochemical measurements and multiple ex-situ studies demonstrate that TiS2 nanoplates are capable of fast and reversible Na+ intercalation and deintercalation. They deliver a large capacity close to full Na+ intercalation (186 mAh/g), high rate capability (~100 mAh/g at 10 C) and satisfactory cycling stability at both low and high current rates. Our study suggest that with proper nanostructure engineering, two-dimensional layered materials may hold great promise as sodium ion battery electrode materials to enable fast and robust energy storage at low costs.