Decorating MnO nanosheets on MOF-derived CoO as a battery-type electrode for hybrid supercapacitors.

Metal-organic framework-derived materials are now considered potential next-generation electrode materials for supercapacitors. In this present investigation, CoO@MnO nanosheets are synthesized using ZIF-67, which is used as a sacrificial template through a facile hydrothermal method. The unique vertically grown nanosheets provide an effective pathway for rapidly transporting electrons and ions. As a result, the ZIF-67 derived CoO@MnO-3 electrode material shows a high specific capacitance of 768 C g at 1 A g current density with outstanding cycling stability (86% retention after 5000 cycles) and the porous structure of the material has a good BET surface area of 160.8 m g. As a hybrid supercapacitor, CoO@MnO-3//activated carbon exhibits a high specific capacitance (82.9 C g) and long cycle life (85.5% retention after 5000 cycles). Moreover, a high energy density of 60.17 W h kg and power density of 2674.37 W kg has been achieved. This attractive performance reveals that CoO@MnO nanosheets could find potential applications as an electrode material for high-performance hybrid supercapacitors.