Hierarchical assembly of manganese dioxide nanosheets on one-dimensional titanium nitride nanofibers for high-performance supercapacitors.

MnO2 has attracted considerable attention for use in supercapacitors. Nevertheless, its low electrical conductivity greatly hinders its potential application. Here, we demonstrate the fabrication of a high-performance electrode material via facile coating of hierarchical MnO2 nanosheets onto highly electrically conductive one-dimensional (1D) TiN nanofibers for use in supercapacitors. The TiN nanofibers are prepared through nitridation electrospinning of TiO2 nanofibers via ammonia annealing. The obtained TiN@MnO2 composites exhibit enhanced electrochemical properties, such as high specific capacitance of 386 F/g at a current density of 1 A/g, and long cycle stability of ∼111.7% capacity retention after 4000 cycles at 6 A/g. The unique nanostructure and significant synergistic effect between TiN and MnO2 are responsible for its good electrochemical performance.