High-performance aqueous symmetric supercapacitor based on polyaniline/vertical graphene/Ti multilayer electrodes

We demonstrate an effective approach to increasing supercapacitor energy and power density by fabricating an aqueous symmetric supercapacitor using polyaniline (PANI)/vertical graphene (VG)/Ti electrodes. The network structure of the PANI nanowires and the porous structure of the VG nanosheets facilitate rapid charge/ion migration and provide additional active sites for ion adsorption/exchange to improve electrochemical performance. The fabricated PANI/VG/Ti electrodes demonstrate high specific capacitance (535.7Fg(-1) at 40Ag(-1) and 461.2Fg(-1) at 50mVs(-1)) and good rate performance in 0.5 M H2SO4 electrolyte. In an aqueous electrolyte, the as-fabricated symmetric supercapacitor exhibits a high energy density of 26.1 W h kg(-1) at a power density of 383 W kg(-1), a high power density of 4.2 kW kg(-1) at an energy density of 6.95 W h kg(-1), and excellent long-term cycling stability with approximately 86% capacitance retention after 10,000 cycles. These results suggest that devices incorporating the proposed PANI/VG/Ti electrode will have significant potential for use in energy storage applications. (C) 2018 Elsevier Ltd. All rights reserved.