© 2014 Elsevier B.V. Ultrathin MnO2 nanosheets arrays on Ni foam have been fabricated by a facile hydrothermal approach and further investigated as the binder-free electrode for high-performance supercapacitors. This unique well-designed binder-free electrode exhibits a high specific capacitance (595.2 F g-1 at a current density of 0.5 A g-1), good rate capability (64.1% retention), and excellent cycling stability (89% capacitance retention after 3000 cycles). Moreover, an asymmetric supercapacitor is constructed using the as-prepared MnO2 nanosheets arrays as the positive electrode and activated microwave exfoliated graphite oxide (MEGO) as the negative electrode. The optimized asymmetric supercapacitor displays excellent electrochemical performance with an energy density of 25.8 Wh kg-1 and a maximum power density of 223.2 kW kg-1. These impressive performances suggest that the MnO2 nanosheet array is a promising electrode material for supercapacitors.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: The authors gratefully acknowledge the financial supports provided by National Natural Science Foundation of China (Grant no. 51104194), National Key laboratory of Fundamental Science of Micro/Nano-device and System Technology (2013MS06, Chongqing University), State Education Ministry and Fundamental Research Funds for the Central Universities (Project nos. CDJZR14135501 and CDJZR13130035, Chongqing University, PR China). The authors acknowledge support on electrochemical characterization by Dr. Kexin Yao in King Abdullah University of Science and Technology, Saudi Arabia.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.