Enhanced stability of Pt nanoparticle electrocatalysts for fuel cells

Although polymer electrolyte membrane fuel cells (PEMFCs) have received broad attention due to their virtually zero emission, high power density, and high efficiency, at present the limited stability of the electrocatalysts used in PEMFCs is a critical limitation to their large-scale commercialization. As a type of popularly used electrocatalyst material, carbon black supported platinum (Pt/C)-although highly efficient-undergoes corrosion of carbon, Pt dissolution, Ostwald ripening, and aggregation of Pt nanoparticles (NPs) under harsh chemical and electrochemical oxidation conditions, which results in performance degradation of the electrocatalysts. In order to overcome these disadvantages, many groups have tried to improve the carbon support materials on which Pt is loaded. It has been found that some novel carbon nanomaterials and noncarbon materials with high surface areas, sufficient anchoring sites, high electrical conductivities, and high oxidation resistance under the strongly oxidizing condition in PEMFCs are ideal alternative supports. This review highlights the following aspects: (i) Recent advances in using novel carbon nanomaterials and noncarbon support materials to enhance the long-term durability of electrocatalysts; (ii) solutions to improve the electrical conductivity, surface area, and the strong interaction between metal and supports; and (iii) the synergistic effects in hybrid supports which help improve the stability of electrocatalysts.