N-doped graphene nanoplatelets as a highly active catalyst for Br2/Br redox reactions in zinc-bromine flow batteries

M. C. Wu, H. R. Jiang, R. H. Zhang, L. Wei, K. Y. Chan, T. S. Zhao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

18 Citations (Scopus)

Abstract

The low power density, due primarily to the sluggish reaction kinetic of Br2/Br, is one of the main barriers that hinder the widespread application of zinc-bromine flow batteries (ZBFBs). Here, N-doped graphene nanoplatelets are synthesized by a facile method and applied as a catalyst for the Br2/Br redox reactions. Electrochemical characterizations reveal that N-doped graphene nanoplatelets exhibit a remarkable catalytic activity toward Br2/Br reactions, thus enabling the ZBFB to achieve an energy efficiency of as high as 84.2% at 80 mA cm−2, far surpassing those with the non-doped counterpart and pristine graphite-felt electrodes. More strikingly, even when the current density is raised up to 120 mA cm−2, the battery can still maintain an energy efficiency of 78.8%, which represents the highest performance for the ZBFBs reported in the open literature. Additionally, the ZBFB with the N-doped graphene nanoplatelets catalyst shows no degradation after 100 cycles. These superior results demonstrate that N-doped graphene nanoplatelets are an efficient and promising catalyst for high-performance bromine-based flow batteries.

Original languageEnglish
Pages (from-to)69-75
Number of pages7
JournalElectrochimica Acta
Volume318
DOIs
Publication statusPublished - 20 Sep 2019
Externally publishedYes

Keywords

  • Br/Br redox reactions
  • Energy storage
  • N-doped graphene nanoplatelets
  • Zinc-bromine flow batteries

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Electrochemistry

Cite this