Cailiao gongcheng (Jan 2019)

Synthesis and capacitive performance of globular MnO<sub>2</sub> flowers anchored graphene composites

  • CHEN Xiang,
  • YAN Shao-jiu,
  • NAN Wen-zheng,
  • WANG Nan,
  • PENG Si-kan,
  • WANG Chen,
  • DAI Sheng-long

DOI
https://doi.org/10.11868/j.issn.1001-4381.2017.001023
Journal volume & issue
Vol. 47, no. 1
pp. 18 – 24

Abstract

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A new type globular MnO2 flowers anchored graphene composites was synthesized via redox reactions among potassium permanganate/ethanol/graphene. The crystalline structure, chemical component, and microstructure of the composites were determined by XRD, TG, SEM/TEM and BET analysis. The electrochemical test demonstrates the globular MnO2 material possesses excellent specific capacitance while poor rate capability and cycling stability. By means of anchoring these globular MnO2 flowers onto graphene, the specific capacitance of graphene is significantly improved. Meanwhile, rate capability and cycling stability of the globular MnO2 material can be promoted remarkably. In 0.5mol/L K2SO4 electrolyte, the specific capacitance of the composites reaches as high as 295F·g-1 at 2mV·s-1, and maintains at 102F·g-1 even at a high scan rate of 1000mV·s-1.An outstanding capacitance retention of 96.3% is achieved for the composites after 1000 cycles at 100mV·s-1. It demonstrates the globular MnO2 flowers anchored graphene composites is a very potential electrode material for supercapacitors.

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