Ionic liquid-modified microporous ZnCoNC-based electrocatalysts for polymer electrolyte fuel cells

Research output: Contribution to journalArticlepeer-review

Authors

  • Min Wang
  • Ihtasham Salam
  • John R. Varcoe
  • Peter Mardle
  • Shichun Mu

Colleges, School and Institutes

External organisations

  • University of Surrey
  • Wuhan University of Technology

Abstract

Non-platinum group metal (non-PGM) oxygen reduction reaction (ORR) catalysts have been widely reported, but their application in proton exchange membrane fuel cells (PEMFCs) is challenging because of their poor performance in acidic environments. Here, [BMIM][NTf2] ionic liquid (IL) modification of microporous ZnCoNC catalysts (derived from ZIF-ZnCo) is investigated to study their behavior in PEMFCs and to elucidate the catalytic mechanisms in practical operation. The high O2 solubility of ILs enhances the utilization of active sites with porous ZnCoNC, and their hydrophobic nature facilitates the water transport during fuel cell operation. The half-cell measurement in aqueous HClO4 shows that with the 20 wt % IL modification, the electron-transfer number increases from 2.58 to 3.88, approaching the desired 4-electron-transfer ORR. The power density obtained shows 140% improvement in single-cell PEMFC tests. The catalyst also yields an interesting performance in alkaline anion-exchange membrane fuel cells.

Details

Original languageEnglish
Pages (from-to)2104-2110
Number of pages7
JournalACS Energy Letters
Volume4
Early online date8 Aug 2019
Publication statusPublished - 13 Sep 2019

Keywords

  • polymer electrolyte fuel cell (PEFC), proton exchange membrane fuel cell (PEMFC), anion exchange membrane fuel cell (AEMFC), CoCN, ZnCoNC, non-PGM, non-platinum group metal, electrocatalyst, ionic liquid, microporous, cathode, durability, oxygen reduction reaction (ORR)