Preparation and capacitance properties of Al-doped hierarchical TiO2 nanostructure by oxidation of Ti–8Al alloy

We reported a facile route for the fabrication of Al-doped TiO 2 nanostructure for supercapacitor electrode materials through an in-situ oxidation of Ti–8Al alloy. Ti–8Al alloy was prepared through solidification route. After high-temperature oxidation, rod-like and wall-like Al-doped TiO 2 composites were formed on the surface of Ti–8Al alloy flake. This kind of novel structure consisted of numerous nanorods and nanosheets, exhibiting large open space. When applied for supercapacitor, Al-doped TiO 2 composites electrode materials exhibited excellent electrochemical performance. After oxidation at 650 °C for 100 h, the electrode can deliver the highest capacitance of 4650 μF cm −2 at the current density of 10 μA cm −2 as well as long-term cycling stability of 98.5% of the initial specific areal capacitance after 6000 cycles.