Hierarchically porous nitrogen-doped carbon derived from the activation of agriculture waste by potassium hydroxide and urea for high-performance supercapacitors

Kaixiang Zou, Yuanfu Deng, Juping Chen, Yunqian Qian, Yuewang Yang, Yingwei Li, Guohua Chen

Research output: Journal article publicationJournal articleAcademic researchpeer-review

118 Citations (Scopus)

Abstract

Nitrogen-doped carbon with an ultra-high specific surface area and a hierarchically interconnected porous structure is synthesized in large scale from a green route, that is, the activation of bagasse via a one-step method using KOH and urea. KOH and urea play a synergistic effect for the enhancement of the specific surface area and the modification of pore size of the as-prepared material. Benefiting from the multiple synergistic roles originated from an ultra-high specific area (2905.4 m2 g−1), a high porous volume (2.05 mL g−1 with 75.6 vol% micropores, which is an ideal proportion of micropores for obtaining high specific capacitance), a suitable nitrogen content (2.63 wt%), and partial graphitization, the hierarchically interconnected porous N-doped carbon exhibits an excellent electrochemical performance with a high specific capacitance (350.8, 301.9, and 259.5 F g−1 at 1.0 A g−1 in acidic, alkaline, and neutral electrolytes, respectively), superior rate capability and excellent cycling stability (almost no capacitance loss up to 5000 cycles). Furthermore, the symmetric device assembled by this material achieves high energy densities of 39.1 and 23.5 Wh kg−1 at power densities of 1.0 and 20 kW kg−1, respectively, and exhibits an excellent long-term cycling stability (with capacitance retention above 95.0% after 10 000 cycles).

Original languageEnglish
Pages (from-to)579-588
Number of pages10
JournalJournal of Power Sources
Volume378
DOIs
Publication statusPublished - 28 Feb 2018

Keywords

  • Activation
  • Biomass waste
  • Hierarchically porous structure
  • Nitrogen-doped carbon
  • Supercapcitors

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Energy Engineering and Power Technology
  • Physical and Theoretical Chemistry
  • Electrical and Electronic Engineering

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