Design and synthesis of 'single-crystal-like' C-doped TiO2 nanorods for high-performance supercapacitors.

Although TiO2 is widely used as a promising electrode material for supercapacitors, its potential application suffers from a critical limitation due to its poor electrical conductivity and low rate capability. Here, we report a cost-effective hydrothermal strategy to design and construct a novel 'single-crystal-like' C-doped TiO2 electrode material. The as-synthesized electrode material combines the advantages of TiO2, 'single-crystal-like' features and carbon doping, considerably improving the electrical conductivity of TiO2. The electrochemical measurements demonstrate that the C-doped TiO2 material presents an excellent specific capacitance (449.8 F g-1 at 1 A g-1), which approaches six times more than the value (77.3 F g-1 at 1 A g-1) of P25 electrodes, and far beyond the value of many previously reported TiO2 electrodes. Therefore, this work explores a new method to design high performance electrochemical TiO2 electrode materials by incorporating other dopants into the TiO2 lattice.