Flexible high-energy asymmetric supercapacitors based on MnO@C composite nanosheet electrodes

Developing asymmetric supercapacitors (ASCs) is a promising alternative to achieve both wide voltage windows and high energy densities to meet the application requirements of hybrid vehicles and renewable energy systems. However, a major limitation of high performance asymmetric supercapacitors lies...

Full description

Saved in:
Bibliographic Details
Published in:Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2017, Vol.5 (2), p.804-813
Main Authors: Yu, Neng, Guo, Kai, Zhang, Wei, Wang, Xianfu, Zhu, Ming-Qiang
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Developing asymmetric supercapacitors (ASCs) is a promising alternative to achieve both wide voltage windows and high energy densities to meet the application requirements of hybrid vehicles and renewable energy systems. However, a major limitation of high performance asymmetric supercapacitors lies in negative electrode materials which possess relatively low specific capacitance compared to positive electrode materials. Herein, a novel MnO@C composite nanosheet array directly grown on conductive carbon cloth as a negative electrode is prepared successfully, which exhibits a large specific capacitance of 662.9 F g −1 at a current density of 3.7 A g −1 and an areal capacitance of 716 mF cm −2 at a current density of 4 mA cm −2 . Afterward, a flexible ASC is successfully assembled with Co 3 O 4 nanosheets and MnO@C nanosheets as the positive electrode and negative electrode, respectively. The optimized ASC achieves a high operating voltage of 1.7 V and displays intriguing performances with a high specific capacitance of 166 F g −1 , an exceptional energy density of 59.6 W h kg −1 and superior rate capability and cycling stability. In addition, the ASC exhibits superior flexibility and mechanical stability even under severe bending states. The ASC based on MnO@C nanosheets as a promising candidate for high performance supercapacitors may pave the way for applications in high performance energy storage systems.
ISSN:2050-7488
2050-7496
DOI:10.1039/C6TA08330G