A hybrid of MnO2 nanowires and MWCNTs as cathode of excellent rate capability for supercapacitors

► Well entangled hybrids of MnO2 nanowires and MWCNTs are obtained by a facile method. ► Their electrochemical performance as cathode for supercapacitors in 0.5 mol l−1 Li2SO4 aqueous electrolyte is reported. ► The energy density (17.8 Wh kg−1) of the supercapacitor stays almost unchanged with power density from 400 to 3340 W kg−1. ► The energy density of the supercapacitor does not fade much after 13,000 cycles.