High-performance asymmetric supercapacitors based on multilayer MnO2 /graphene oxide nanoflakes and hierarchical porous carbon with enhanced cycling stability.
In this work, MnO(2)/GO (graphene oxide) composites with novel multilayer nanoflake structure, and a carbon material derived from Artemia cyst shell with genetic 3D hierarchical porous structure (HPC), are prepared. An asymmetric supercapacitor has been fabricated using MnO(2)/GO as positive electrode and HPC as negative electrode material. Because of their unique structures, both MnO(2)/GO composites and HPC exhibit excellent electrochemical performances. The optimized asymmetric supercapacitor could be cycled reversibly in the high voltage range of 0-2 V in aqueous electrolyte, which exhibits maximum energy density of 46.7 Wh kg(-1) at a power density of 100 W kg(-1) and remains 18.9 Wh kg(-1) at 2000 W kg(-1). Additionally, such device also shows superior long cycle life along with ∼100% capacitance retention after 1000 cycles and ∼93% after 4000 cycles.
Key Laboratory of Applied Chemistry, Yanshan University, Qinhuangdao, 066004, China.
Yufeng
Y
Zhao
Wei
W
Ran
Jing
J
He
Yizhong
Y
Huang
Zhifeng
Z
Liu
Wei
W
Liu
Yongfu
Y
Tang
Long
L
Zhang
Dawei
D
Gao
Faming
F
Gao
MnO2; carbon; composites; electrochemical performance; supercapacitors