Chemical Engineering Journal, Vol.326, 518-527, 2017
Honeycomb-like composite structure for advanced solid state asymmetric supercapacitors
Three dimension honeycomb-like porous hybrid material (3DHPC-NiCo2S4), which was assembled from interconnection carbon nanosheets covering vertical NiCo2S4 nanosheets, was fabricated using one-step carbonization cellulose followed by hydrothermal process and sulfidation. As supercapacitor electrode, the composites show excellent capacitance performance resulting from interconnection carbon nanosheets as power component and multivalent metal sulfides NiCo2S4 nanosheets as energy component. The synergetic effect leads to 1168 and 684 F/g at current densities of 1 and 20 A/g at three-electrode system, respectively. The composite of Fe2O3 nanorods and honeycomb-like carbon materials was prepared (3DHPC-Fe2O3) with similar method. Solid state asymmetric supercapacitor fabricated with 3DHPC-Fe2O3 as negative and 3DHPC-NiCo2S4 as positive electrode (3DHPC-NiCo2S4//3DHPC-Fe2O3) can delivered a superior gravimetric energy density of 44.4 Wh/kg (volumetric energy density of 1.71 mWh/cm(3)) at 1.62 KW/kg (volumetric power density 62.94 mW/cm(3)) and outstanding cycling stability (88.5% retention after 10,000 cycles). (C) 2017 Elsevier B.V. All rights reserved.