Premium
Advanced Asymmetric Supercapacitors Based on Ni(OH) 2 /Graphene and Porous Graphene Electrodes with High Energy Density
Author(s) -
Yan Jun,
Fan Zhuangjun,
Sun Wei,
Ning Guoqing,
Wei Tong,
Zhang Qiang,
Zhang Rufan,
Zhi Linjie,
Wei Fei
Publication year - 2012
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201102839
Subject(s) - supercapacitor , graphene , materials science , capacitance , electrode , power density , nanotechnology , electrochemistry , energy storage , porosity , chemical engineering , optoelectronics , composite material , power (physics) , chemistry , physics , quantum mechanics , engineering
Hierarchical flowerlike nickel hydroxide decorated on graphene sheets has been prepared by a facile and cost‐effective microwave‐assisted method. In order to achieve high energy and power densities, a high‐voltage asymmetric supercapacitor is successfully fabricated using Ni(OH) 2 /graphene and porous graphene as the positive and negative electrodes, respectively. Because of their unique structure, both of these materials exhibit excellent electrochemical performances. The optimized asymmetric supercapacitor could be cycled reversibly in the high‐voltage region of 0–1.6 V and displays intriguing performances with a maximum specific capacitance of 218.4 F g −1 and high energy density of 77.8 Wh kg −1 . Furthermore, the Ni(OH) 2 /graphene//porous graphene supercapacitor device exhibits an excellent long cycle life along with 94.3% specific capacitance retained after 3000 cycles. These fascinating performances can be attributed to the high capacitance and the positive synergistic effects of the two electrodes. The impressive results presented here may pave the way for promising applications in high energy density storage systems.