Nanostructured 3D zinc cobaltite/nitrogen-doped reduced graphene oxide composite electrode for supercapacitor applications

This paper reports the electrochemical performance of a binder-free supercapacitor electrode based on ZnCo2O4 nanoflakes and N-doped reduced graphene oxide (rGO). The morphology of ZnCo2O4 was tailored by changing the substrate from bare Ni foam (NiF) to rGO-supported NiF and then to N-doped rGO-supported NiF. The N-doped electrode exhibited superior electrochemical performance, i.e., high specific capacitance (1613 Fg(-1) at 1 Ag-1) and excellent cycling stability (97.3% after 5000 cycles). An asymmetric supercapacitor based on this nanohybrid exhibited a high energy density of 36.5 Wh kg(-1) This excellent electrochemical performance highlights the potential of this electrode for next-generation supercapacitors. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.