A polyaniline/titanium nitride (PANI/TiN) nanotube hybrid was prepared and used for an electrochemical supercapacitor application. Firstly, the well-aligned TiN nanotube array was prepared by anodization of titanium foil and subsequent nitridation through ammonia annealing. Then, PANI was deposited into TiN nanotube through the electrochemical polymerization process. The obtained PANI/TiN nanotube hybrid had an ordered porous structure. A high specific capacitance of 1,066 F g−1 was obtained at the charge–discharge current density of 1 A g−1 when only the mass of PANI was considered. The specific capacitance can even achieve 864 F g−1 at 10 A g−1 and still keep 93 % of the initial capacity after 200 cycles. An aqueous supercapacitor, consisting of two symmetric PANI/TiN nanotube hybrid electrodes and 1.0 M H2SO4 electrolyte solution, showed the specific capacitance of 194.8 F g−1, energy density of 9.74 Wh kg−1, and power density of 0.3 kW kg−1.
