Scalable Construction of Heteroatoms-Doped and Hierarchical Core-Shell MnO2 Nanoflakes on Mesoporous Carbon for High Performance Supercapacitor Device
A highly ordered N, S–codoped mesoporous carbon (NSMC) is fabricated via sacrifice template method followed by facile doping reaction. Thanks to the uniform mesoporous channels, NSMC exhibits a high specific capacitance of 298 F g‒1. Moreover, the MnO2 nanosheets deposited onto mesoporous carbon channels is performed via solvothermal reaction. By controlling reaction time, various composites and the corresponding electrochemical performance are obtained. The maximum capacitance of MnO2@mesoporous carbon (MnO2@MC) is 310 F g‒1. An asymmetric device using NSMC as negative electrode and MnO2@MC–30 as a positive electrode is assembled. The assembled supercapacitor can deliver a maximum energy density of 44.0 Wh kg‒1 with a high power density of 12000 W kg‒1 plus outstanding cycling stability of 90% after 5000 cycles. This work combines interfacial methods with mesoporous carbon channels, providing new insights for the design of high-performance electrode materials.