In situ construction of Ir@Pt/C nanoparticles in the cathode layer of membrane electrode assemblies with ultra-low Pt loading and high Pt exposure

JOURNAL OF POWER SOURCES

卷:355

Article

Dang, Dai^1,2  Zhang, Lei³  Zeng, Xiaoyuan^1,2  Tian, Xinlong^1,2  Qu, Chong³  Nan, Haoxiong^1,2  Shu, Ting^1,2  Hou, Sanying^1,2  Yang, Lijun^1,2  Zeng, Jianhuang^1,2  Liao, Shijun^1,2 

[1] South China Univ Technol, Key Lab Fuel Cell Technol Guangdong Prov, Sch Chem & Chem Engn, Guangzhou 510641, Guangdong, Peoples R China

[2] South China Univ Technol, Key Lab New Energy Technol Guangdong Univ, Guangzhou 510641, Guangdong, Peoples R China

[3] Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA

关键词: Ultra-low Pt loading;    Core-shell structure;    Membrane electrode assembly;    Fuel cell;    DFT;   

DOI  :  10.1016/j.jpowsour.2017.04.050

来源: Elsevier

【 摘 要 】

A novel membrane electrode assemblies (MEAs) with ultra-low Pt loadings and high Pt exposure in the cathode layer is prepared by spraying Ir/C catalyst ink on the membrane surface to form a substrate layer, followed by in situ pulse electrochemical deposition of a Pt shell layer on the Ir core nanoparticles in the substrate layer. It makes the Pt loadings on cathode lower to 0.044 mg/cm(2). In our system, the MEA with our novel cathode exhibits excellent performance in a H-2/air single fuel cell, which is comparable to that of the MEA prepared with commercial Pt/C catalyst (Johnson Matthey 40% Pt) with Pt loadings of 0.1 mg/cm2. The electrode with core shell structured catalysts is characterized by X-ray diffraction, X-ray photoelectron spectroscopy, EDS line-scan, and scanning transmission electron microscopy. Based on the characterization results, it is found that the Pt is highly dispersed on the Ir NPs, and the electronic feature of Pt at shell layer can be tuned by the Ir core particle. Furthermore, the DFT calculation results also reveal the interaction between Pt at shell layer and Ir core. This work may provide a novel pathway to realize low Pt and high Pt utilization in low temperature fuel cells. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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