MnO2 Nanoparticle Improved Cyclic Stability of Carbon Fiber Cloth Supported NiO Battery-Type Supercapacitor Materials by Microwave Solid-State Method

MnO2 nanoparticles were rapidly grown on a carbon fiber cloth (CFC) substrate via microwave solid-state synthesis and used as an electrode material to improve the cycling stability of NiO battery-type supercapacitors. The morphology and electrochemical properties of NiO@CFC and NiO/MnO2@CFC composites were characterised, and the electrochemical properties of the electrode materials prepared under different feeding qualities and microwave conditions were compared. NiO/MnO2@CFC showed a high specific capacitance of 188.3 mAh/g at a current density of 1 A/g and excellent cycling stability (capacity retention of 88.4% after 2000 cycles); these results indicate that the MnO2 nanoparticles improve the cycling stability of CFC-supported NiO supercapacitors (37.8% capacitance loss after 1000 cycles). An asymmetric NiO/MnO2@CFC supercapacitor revealed a competitive energy density of 20.87 Wh/kg at a power density of 850 W/kg. The successful design and synthesis of these composites via the microwave-assisted solid-state method provides a novel strategy for preparing electrode materials for high-performance energy storage devices. (C) 2019 The Electrochemical Society.