High Performance Supercapacitor Electrodes Based On Metal/Metal-Oxide Core/Shell Nano-Heterostructures

摘要

This study demonstrates the fabrication technique of novel nano-heterostructures (NHs) and their comparative study of electrochemical performance as supercapacitor electrodes. The fabricated Ni/NiO core/shell and Co-Ni/Co_3O_4-NiO core/shell nano-heterostructures supercapacitor electrodes offer the desired properties of macroporosity to allow facile electrolyte flow, thereby reducing device resistance and nanoporosity with large surface area to allow faster reaction kinetics. In three electrode configuration, Ni/NiO core/shell and Co-Ni/Co_3O_4-NiO core/shell nano-heterostructures supercapacitor electrodes exhibited specific capacitance values (731 and 2013 F g~(-1), respectively, at a constant current density of 2.5 A g~(-1)), high energy (36.5 and 44.7 Wh kg~(-1), respectively), power density (7.5 and 5.6 kW kg~(-1), respectively), good capacitance retention and long cyclicality. The remarkable electrochemical property of the large surface area nano-heterostructures is demonstrated based on the effective nano-architectural design of the electrode with the coexistence of the highly redox active materials at the surface supported by highly conducting metal channel at the core for faster charge transport.