Performance of an ultra-low platinum loading membrane electrode assembly prepared by a novel catalyst-sprayed membrane technique

• Published in: Journal of power sources Vol. 195; no. 3; pp. 756 - 761
• Main Authors: Su, Hua-Neng, Liao, Shi-Jun, Shu, Ting, Gao, Hai-Li
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2010; Elsevier
• Subjects: Applied sciences; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; High performance; Membrane electrode assembly; Nafion content; Polymer electrolyte membrane fuel cell; Ultra-low platinum loading; High performance; Polymer electrolyte membrane fuel cell; Nafion content; Membrane electrode assembly; Ultra-low platinum loading; Measurement; Scanning electron microscopy; Costs; Polymer electrolytes; Cathode; Thin film; Platinum; Membrane; Performance; Catalyst; Fuel cell; Electrochemical impedance spectroscopy
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2009.08.037

Membrane electrode assemblies (MEAs) with ultra-low platinum loadings are attracting significant attention as one method of reducing the quantity of precious metal in polymer electrolyte membrane fuel cells (PEMFCs) and thereby decreasing their cost, one of the key obstacles to the commercialization of PEMFCs. In the present work, high-performance MEAs with ultra-low platinum loadings are developed using a novel catalyst-sprayed membrane technique. The platinum loadings of the anode and cathode are lowered to 0.04 and 0.12 mg cm −2, respectively, but still yield a high performance of 0.7 A cm −2 at 0.7 V. The influence of Nafion content, cell temperature, and back pressures of the reactant gases are investigated. The optimal Nafion content in the catalyst layer is ca. 25 wt.%. This is significantly lower than for low platinum loading MEAs prepared by other methods, indicating ample interfacial contact between the catalyst layer and membrane in our prepared MEAs. Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) measurements reveal that our prepared MEA has very thin anode and cathode catalyst layers that come in close contact with the membrane, resulting in a MEA with low resistance and reduced mass transport limitations.