Supercapacitance performance of polypyrrole/titanium nitride/polyaniline coaxial nanotube hybrid

The polypyrrole/titanium nitride/polyaniline (PPy/TiN/PANI) coaxial nanotube hybrid has been prepared as supercapacitor electrode material by stepwise loading of PPy and PANI into TiN nanotube array through normal pulse voltammetry and cyclic voltammetry electrodeposition process. P-type doping PPy and N-type doping PANI could be well incorporated into an integrated composite to act as an electroactive material. TiN nanotube array with highly ordered nanostructure and good electrical conductivity promoted the charge transfer capability of conducting polymers of PPy and PANI. PPy/TiN/PANI coaxial nanotube hybrid with P/N type doping properties exhibited high specific capacitance of 1471.9 F g−1 at a current density of 0.5 A g−1 and a potential window of 0.8 V in 1.0 M H2SO4 solution. It could keep the capacitance of 1077.4 F g−1 at high current density of 10 A g−1 and capacitance retention of 78.0% after 200 cycles, presenting good rate capability and reasonable cycling stability. All-solid-state flexible supercapacitor was constructed using PPy/TiN/PANI electrode and H2SO4-included polyvinylalcohol gel electrolyte. It offered superior energy storage capacity with respect to specific capacitance of 288.4 F g−1 and energy density of 129.8 Wh kg−1 at high potential window of 1.8 V and current density of 1.0 A g−1. PPy/TiN/PANI coaxial nanotube hybrid accordingly presented the promising application as supercapacitor electrode material for energy storage.