Ionic liquid modified Pt/C electrocatalysts for cathode application in proton exchange membrane fuel cells

Abstract

The modification of Pt/C catalyst by using ionic liquids to improve their catalyst activities has been reported by many researchers, but their practical behavior in operating fuel cells is still unknown. In this work, we study the ionic liquid modified Pt/C nanoparticle catalysts within cathodes for proton exchange membrane fuel cells. The influence of the ionic liquid amount, adsorption times and dispersing solvents are investigated. The experiment results show the best performance enhancement is achieved through two-time surface modification with 2 wt-% ionic liquid solution. The mechanisms are explored with the attribution to the high oxygen solubility in the ionic liquid enabling an improved oxygen diffusion in micropores and to good hydrophobicity facilitating water expelling from the active sites in fuel cell operation.

Graphical abstract

Keywords

ionic liquid / PEMFC / electrode / oxygen reduction reaction / electrocatalyst / adsorption

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Acknowledgements

Zhang H X is funded by EU H2020 Marie Skłodowska-Curie Fellowship (739940). Thanks are also to the support from Guangdong Academy of sciences project (2019 GDASYL-0503005).

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2019 The Author(s) 2019. This article is published with open access at link.springer.com and journal.hep.com.cn