Fuel cell performance of membrane electrode assembly with PDAC/sPPO self-assembly layer containing Pt-Ru catalyst on proton exchange membrane surface

摘要

In this study, 5, 10, and 15 bi-layers of poly(diallyl dimethyl ammonium chloride) (PDAC)/sulfonatedpoly(2,6-dimethyl 1,4-phenylene oxide) (sPPO) containing Pt-55-Ru-45 catalyst are self-assembled on both sides of the proton exchange membrane (PEM) (i.e. Nafion-117) using a layer-by-layer technique to serve as the membrane electrode assembly (MEA) for a direct methanol fuel cell (DMFC). Experimental results show that the XC-72 carbon particles with Pt55-Ru45 alloy catalyst in the sPPO layer penetrated the PDAC layers forming a continuous catalyst layer throughout the self-assembly PDAC/sPPO bi-layers. This continuous catalyst layer structure provides a conductive media and transfer channel for the produced electrons and protons in the catalyst layer to the external circuit and the PEM and cathode sides. Our self assembly MEAs have higher mass catalyst activity than the MEA prepared by the conventional method under CH3OH/O-2 fuel cell testing, i.e., 1588.8 (5 bi-layers), 1205.8 (10 bi-layers), and 350.0A g(-1) Pt-Ru (15 bi-layers) vs. 80.0A g(-1) Pt-Ru (for conventional MEA), respectively. The 10 bi-layers of PDAC/sPPO sample loaded with 0.017 mg Pt-Ru cm-2 catalyst had the highest power density of 3.70 mW cm-2 (@0.18 V) and 74.1 mW cm(-2) (@0.40 V) under the CH3OH/O-2 and H-2/O-2 fuel cell operating at 80 degrees C, respectively. (C) 2016 Elsevier B.V. All rights reserved.