A flexible hybrid capacitor based an NiCo₂S₄ nanowire electrode with an ultrahigh capacitance

It is well-known that the excellent cycling stability and high energy density of electrode materials is very important for supercapacitors. However, their actual performance falls far behind and does not satisfy the practical demand. In this study, we synthesized NiCo₂S₄ nanowire bundles on a nickel foam via facile hydrothermal routes. The as-obtained product as an electrode material possesses excellent specific surface area, which suggests that numerous active sites on the electrode surface can shorten the diffusion channel of ions. The assembled asymmetric supercapacitor delivers an energy density of 57.36 W h kg^-1 at 1412.92 W kg^-1. Also, it exhibits excellent mechanical stability even at different bending angles.