Electrochemical Capacitance Performance of Hybrid Supercapacitors Based on Ni(OH)[sub 2]∕Carbon Nanotube Composites and Activated Carbon

Abstract

carbon nanotube (MWNT) nanocomposites were synthesized by in situ loading on the carbon nanotubes in an alkaline solution. The effects of the added carbon nanotubes on the morphology and electrochemical capacitance of were investigated in various loaded amounts of . The MWNT substrates can reduce the aggregation of nanoparticles, inducing a good distribution of the nanosized particles on the cross-linked, netlike structure MWNTs. As a result, the rate capability and utilization of was greatly improved, and the composite electrode resistance was reduced. Under the optimal 70% mass load of in the composite, the capacity of the composite is at a current density of between 0 and 0.4 V vs SCE. The hybrid supercapacitor based on such composite positive electrodes and activated carbon negative electrodes delivered a specific energy of at a specific power of based on the total weight of the active electrode materials. It also exhibited good cycling performance and kept 90% of its initial capacity for over 2000 cycles.