MnO2 nanorods/MXene/CC composite electrode for flexible supercapacitors with enhanced electrochemical performance

In this paper, a highly deformable and conductive freestanding electrode based on the composite of MnO2 and MXene on carbon cloth is designed. Benefiting from the synergistic coupling of MXene and MnO2, the novel electrode has enhanced electrochemical performance (511.2 F/g) compared with MnO2 nanorods/carbon cloth (302.3 F/g), and when the current increases by 5 times (1 A/g to 5 A/g), 60.3% capacitance was retained, suggesting excellent rate capability. The capacitance of the composite electrode was reduced by only 17% after 10,000 cycles, showing excellent cycle stability. In addition, an asymmetric flexible supercapacitor based on MnO2 nanorods/MXene/carbon cloth exhibited a high energy density of 29.58 Wh/kg at a power density of 749.92 W/kg. The assembled supercapacitor presented excellent mechanical properties, even if the capacitor is bent 180°, the performance is almost unchanged. The above results demonstrate that MnO2/MXene/CC electrode has a potential for high-performance flexible supercapacitors.