Ionic liquid modified Pt/C electrocatalysts for cathode application in proton exchange membrane fuel cells
Huixin Zhang1,2, Jinying Liang1, Bangwang Xia2, Yang Li1, Shangfeng Du1()
1. School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK 2. School of Chemical Engineering, Hebei University of Technology, Tianjin 300130, China
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.
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