Enhance supercapacitive performance of MnO2/3D carbon nanotubes-graphene as a binder-free electrode

• Published in: Journal of alloys and compounds Vol. 787; pp. 759 - 766
• Main Authors: Bi, Tiantian, Fang, Huaqing, Jiang, Jinlong, He, XingXing, Zhen, Xuan, Yang, Hua, Wei, Zhiqiang, Jia, Zhengfeng
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 30.05.2019; Elsevier BV
• Subjects: 3D carbon nanotubes-graphene; Carbon; Carbon nanotubes; Chemical vapor deposition; Copper; Defects; Electrodes; Energy storage; Graphene; Manganese dioxide; Manganese oxide; Metal foils; Nanocomposites; Nanoparticles; Organic chemistry; Sodium sulfate; Substrates; Supercapacitor; Thermal decomposition; 3D carbon nanotubes-graphene; Supercapacitor; Thermal decomposition; Manganese oxide
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.02.117

In this paper, the MnO2/three-dimensional carbon nanotubes-graphene nanocomposite was synthesized on Cu foil substrate by chemical vapor deposition and subsequent thermal decomposition of manganese acetyllacetonate precursors. The nanocomposite material was directly used as a binder-free electrode to investigate the supercapacitive performance. The results indicate that the appropriate defects and MnO2 nanoparticles are introduced simultaneously into the carbon nanotubes-graphene architecture in one-step. The specific capacitance of MnO2/three-dimensional carbon nanotubes-graphene/Cu electrode is up to 365 F g−1 at a current density of 1 A g−1 in 1.0 M Na2SO4 solution, which is 9 times higher than that of electrode without MnO2 modification. After 1000 cycles at 1 A g−1, the capacity retention is still maintained at 97.0%, suggesting potential applications in high-performance energy storage devices. The excellent electrochemical performances of nanocomposite electrode can be attributed to the significantly synergistic effects between the lasting electronic conductivity of three-dimensional carbon nanotubes-graphene/Cu with the appropriate defects and the pseudocapacitance of the MnO2 nanoparticles. [Display omitted] •MnO2/3D CNTs-G/Cu was fabricated as a binder-free electrode using a facile method.•Defects and α-MnO2 was introduced simultaneously into the 3D CNTs-G/Cu in one-step.•The specific capacitance of MnO2/3D CNTs-G/Cu reached 365 F g−1 at 1 A g−1 current.•Synergistic effects of 3D CNTs-G/Cu lasting conductivity and MnO2 pseudocapacitance.