화학공학소재연구정보센터
Electrochimica Acta, Vol.283, 438-447, 2018
High performance advanced asymmetric supercapacitor based on ultrathin and mesoporous MnCo2O4.5-NiCo2O4 hybrid and iron oxide decorated reduced graphene oxide electrode materials
Herein, we demonstrate a facile fabrication of nickel cobalt oxide nanoflake decorated manganese cobalt oxide nanostick-arrays (MnCo2O4.5-NiCo2O4), as a hybrid electrode material through multistep hydrothermal protocols for high performance power device applications. Iron oxide nanoparticles decorated reduced graphene oxide (Fe-rGO) was synthesized through a simplistic reduction process of GO. The morphological features, specific surface areas and morphology dependent electrochemical activity of the as-prepared electrode materials have been investigated systematically. Our as-prepared manganese cobalt oxide/nickel cobalt oxide, MnCo2O4.5-NiCo2O4 (abbreviated as MCO/NCO) hybrid electrode reveals a highest specific capacitance (C-s) value of similar to 2506 Fg(-1) as compared to the base MnCo2O4.5 (similar to 1220 Fg(-1)) at 1 Ag-1 constant current density. The higher C-s values of the hybrid composite can be credited to the synergistic property of MCO and NCO, which eventually facilitates electron transportation. In contrast, Fe-rGO shows a C-s value of similar to 236 Fg(-1) at l Ag-1. Moreover, an advanced asymmetric supercapacitor (ASC) device was fabricated utilizing MCO/NCO as positive and Fe-rGO as a negative electrode in presence of a potassium hydroxide (KOH) soaked laboratory Whatman 40 filter paper as separator. The device exhibits a C-s value of 170.8 Fg(-1) at 1 Ag-1 together with a decent energy density of similar to 34 Wh kg(-1) (power density of 597.18 Wkg(-1) at 1 Ag-1) and a longtime cyclic stability (90% C-s retention after 3000 Galvanostatic charge-discharge series). These results suggest superior application potential of our ASC for next -generation portable energy storage applications. (C) 2018 Elsevier Ltd. All rights reserved.