High-performance flexible solid-state supercapacitors based on MnO2-decorated nanocarbon electrodes

Authors

Yang Gao, University of Nebraska-Lincoln
Yun Shen Zhou, University of Nebraska-Lincoln
Min Qian, University of Nebraska-LincolnFollow
Hao Ming Li, East China Normal University
Jody G. Redepenning, East China Normal UniversityFollow
Li Sha Fan, University of Nebraska-Lincoln
Xiang Nan He, University of Nebraska-Lincoln
Wei Xiong, University of Nebraska-Lincoln
Masoud Majhouri-Samani, University of Nebraska-Lincoln
Lan Jiang, Beijing Institute of Technology
Yongfeng Lu, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2013

Citation

Published in RSC Adv. (2013) 3: 20613. DOI: 10.1039/c3ra43039a

Comments

© 2013 The Royal Society of Chemistry. Used by Permission.

Abstract

Flexible energy storage units are highly desired to meet the ever-increasing demands for flexible electronics. In this paper, highly flexible solid-state supercapacitors are fabricated using MnO₂-decorated nanocarbon electrodes and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide–poly(vinylidene fluoride)- hexafluoropropylene ([EMIM][NTf2]–PVdF(HFP)) gel electrolytes. The flexible electrodes are prepared by electrodepositing MnO₂ onto the carbon nanotube/carbon nanoonion (CNT/CNO) films. CNT/CNO films have a large surface area for MnO₂ deposition and work as mechanical supports with high flexibility and light weight. CNOs act as spacers to separate CNTs, introducing mesopores inside the CNT/CNO films for preventing pore blocking during MnO₂ deposition. The supercapacitor exhibits enhanced electrochemical performance with an energy density of 16.4 W h^-1 kg^-1 at a power density of 33.3 kW kg^-1 by using the [EMIM][NTf2]–PVdF(HFP) gel electrolyte. Moreover, the supercapacitors can exhibit high electrochemical performance under large mechanical stress, making the devices suitable for flexible electronics.