Significant improvement in cathode performance for proton exchange membrane fuel cell by a novel double catalyst layer design

Conventional double catalyst layer (DCL) structures show no obvious improvement in cathode performance, due to the contradiction between improving mass transfer and maintaining good platinum (Pt) utilization. To decrease this conflict, a novel DCL cathode is prepared using catalysts with two different amounts of Pt; the catalyst with higher Pt content is used in the inner layer to concentrate the Pt, and the catalyst containing less Pt is used in the outer layer to maintain a suitable layer thickness. Polarization characteristics of cathodes with this novel DCL, a conventional DCL, and a single catalyst layer (SCL) are evaluated at ambient pressure in an H-2/air PEMFC. The results show a significant increase in performance with the novel DCL cathode. Compared with the SCL cathode, the current density of the novel DCL cathode at 0.6V increases by 35.9%, while that of the conventional DCL cathode increases by just 8.8%. (C) 2009 Elsevier B.V. All rights reserved.