Controlled synthesis of cobalt carbonate/graphene composites with excellent supercapacitive performance and pseudocapacitive characteristics

Mohammad Akbari Garakani, Sara Abouali, Biao Zhang, Zheng Long Xu, Jiaqiang Huang, Jian Qiu Huang, Elham Kamali Heidari, Jang Kyo Kim

Research output: Journal article publicationJournal articleAcademic researchpeer-review

36 Citations (Scopus)

Abstract

Cobalt carbonate hydroxide/graphene aerogel and cobalt carbonate/graphene aerogel (CCH/GA and CC/GA) composites are synthesized as supercapacitor electrodes via a one-pot hydrothermal method. Optimized processing conditions are established by controlling the composite composition and microstructure, and their influence on the capacitance performance of the electrodes is identified. A remarkable specific capacitance of 1134 F g-1at a current density of 1 A g-1is obtained for the optimal nanowire-shaped CCH/GA electrode, which is among the highest capacitance values of cobalt compound electrodes with or without nanocarbons reported so far. The electrode also delivers exceptional rate performance and cyclic stability benefiting from the pseudocapacitive characteristics of CC-based active materials and the highly conductive, interconnected 3D-structured GA. The CC/GA electrode presents a high capacity of 731 F g-1under the same conditions. The ex situ XPS analysis identifies the reversible redox reactions of cobalt cations during charge/discharge cycles as the electrochemical mechanism responsible for the high pseudocapacitive properties of CC-based electrodes.
Original languageEnglish
Pages (from-to)17827-17836
Number of pages10
JournalJournal of Materials Chemistry A
Volume3
Issue number34
DOIs
Publication statusPublished - 21 Jul 2015
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)

Cite this