title: Facile Synthesis of Hierarchical Mesoporous Honeycomb-like NiO for Aqueous Asymmetric Supercapacitors.
abstract: Three-dimensional (3D) hierarchical nanostructures have been demonstrated as one of the most ideal electrode materials in energy storage systems due to the synergistic combination of the advantages of both nanostructures and microstructures. In this study, the honeycomb-like mesoporous NiO microspheres as promising cathode materials for supercapacitors have been achieved using a hydrothermal reaction, followed by an annealing process. The electrochemical tests demonstrate the highest specific capacitance of 1250 F g(-1) at 1 A g(-1). Even at 5 A g(-1), a specific capacitance of 945 F g(-1) with 88.4% retention after 3500 cycles was obtained. In addition, the 3D porous graphene (reduced graphene oxide, rGO) has been prepared as an anode material for supercapacitors, which displays a good capacitance performance of 302 F g(-1) at 1 A g(-1). An asymmetric supercapacitor has been successfully fabricated based on the honeycomb-like NiO and rGO. The asymmetric supercapacitor achieves a remarkable performance with a specific capacitance of 74.4 F g(-1), an energy density of 23.25 Wh kg(-1), and a power density of 9.3 kW kg(-1), which is able to light up a light-emitting diode.
authors: College of Materials Science and Engineering, Taiyuan University of Technology , Taiyuan, Shanxi 030024, P. R. China.
authors: Xiaochuan
authors: X
authors: Ren
authors: College of Materials Science and Engineering, Taiyuan University of Technology , Taiyuan, Shanxi 030024, P. R. China.
authors: Chunli
authors: C
authors: Guo
authors: Key Laboratory of Colloid & Interface Chemistry, Ministry of Education and School of Chemistry and Chemical Engineering, Shandong University , Jinan, Shandong 235000, P. R. China.
authors: Liqiang
authors: L
authors: Xu
authors: College of Materials Science and Engineering, Taiyuan University of Technology , Taiyuan, Shanxi 030024, P. R. China.
authors: Taotao
authors: T
authors: Li
authors: College of Materials Science and Engineering, Taiyuan University of Technology , Taiyuan, Shanxi 030024, P. R. China.
authors: Lifeng
authors: L
authors: Hou
authors: College of Materials Science and Engineering, Taiyuan University of Technology , Taiyuan, Shanxi 030024, P. R. China.|School of Chemistry and Chemical Engineering, Lvliang College , Lishi Shanxi 033000, China.
authors: Yinghui
authors: Y
authors: Wei
keywords: 3D porous graphene; NiO; asymmetric supercapacitor; mesopores; self-assembling