Volume 6 Issue 5
Oct.  2021
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Article Contents
Shengnan Li, Shih-Hsin Ho, Tao Hua, Qixing Zhou, Fengxiang Li, Jingchun Tang. Sustainable biochar as an electrocatalysts for the oxygen reduction reaction in microbial fuel cells. Green Energy&Environment, 2021, 6(5): 644-659. doi: 10.1016/j.gee.2020.11.010
Citation: Shengnan Li, Shih-Hsin Ho, Tao Hua, Qixing Zhou, Fengxiang Li, Jingchun Tang. Sustainable biochar as an electrocatalysts for the oxygen reduction reaction in microbial fuel cells. Green Energy&Environment, 2021, 6(5): 644-659. doi: 10.1016/j.gee.2020.11.010

Sustainable biochar as an electrocatalysts for the oxygen reduction reaction in microbial fuel cells

doi: 10.1016/j.gee.2020.11.010
  • Microbial fuel cells (MFCs) have gained remarkable attention as a novel wastewater treatment that simultaneously generates electricity. The low activity of the oxygen reduction reaction (ORR) remains one of the most critical bottlenecks limiting the development of MFCs. To date, although research on biochar as an electrocatalyst in MFCs has made tremendous progress, further improvements are needed to make it economically practical. Recently, biochars have been considered to be ORR electrocatalysts with developmental potential. In this review, the ORR mechanism and the essential requirements of ORR catalysts in MFC applications are introduced. Moreover, the focus is to highlight the material selection, properties, and preparation of biochar electrocatalysts, as well as the evaluation and measurement of biochar electrodes. Additionally, in order to provide comprehensive information on the specific applications of biochars in the field of MFCs, their applications as electrocatalysts, are then discussed in detail, including the uses of nitrogen-doped biochar and other heteroatom-doped biochars as electrocatalysts, poisoning tests for biochar catalysts, and the cost estimation of biochar catalysts. Finally, profound insights into the current challenges and clear directions for future perspectives and research are concluded.

     

  • • The essential requirements of ORR catalysts suitable for MFCs were proposed. • The effects of biochar and electricity generation in MFCs were summarized. • Biochar as an electrocatalyst is active for catalysing the ORR. • Challenges and future prospects of biochar as ORR catalysts were directed.
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