Progress of Pt-Based Catalysts in Proton-Exchange Membrane Fuel Cells: A Review

Abstract

Fuel cells are energy conversion devices that convert chemical energy directly into electricity. It has the advantages of high energy density, high utilization efficiency of fuel, clean and noiseless during working. Among all kinds of fuel cells, proton exchange membrane fuel cells (PEMFCs) are most popular since PEMFCs function at near ambient temperature, while their power densities are higher than those of other fuel cells. Currently, Pt-based nanomaterials are still the unreplaceable catalysts in commercialized PEMFCs. The lack of low-cost and high-performance cathode catalysts is still one of key factors that hampers the commercialization of PEMFCs. In this review, the structurally controlled syntheses of catalysts and their influences on the performances of oxygen reduction reaction (ORR) and membrane electrode assembly (MEA) are summarized. The performance of membrane electrode assembly (MEA) can also be adjusted by regulating the structure of catalyst layer. Special attention has been paid with a focus on the achievement of enhanced utilization of noble metal, and thus, lowering the loading of noble metals in MEA.

Keywords

proton-exchange membrane fuel cells / Pt-based catalysts / catalyst layer / membrane electrode assembly

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