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DOE OSTI · 1848388

Highly stable and ordered intermetallic PtCo alloy catalyst supported on graphitized carbon containing Co@CN for oxygen reduction reaction

Jung, Won Suk·Lee, Woong Hee·Oh, Hyung-Suk·Popov, Branko N.
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Abstract

A PtCo alloy catalyst was prepared by thermal diffusion of Co encapsulated with thin N-doped carbon layers on graphitic carbon into a Pt lattice (PtCo/NGC). The Co diffused up to the near-Pt surface and resulted in an intermetallic PtCo structure without the leaching process. The intermetallic PtCo structure thermally treated under optimized conditions showed 3-fold higher mass activity than the commercial Pt/C. The potential and maximum power density loss of PtCo/NGC after 30 000 potential cycles were 34 mV and 11%, respectively, which indicated that the PtCo/NGC was remarkably stable when compared to commercial Pt/C and commercial PtCo/GC catalysts. The enhanced catalytic performance and stability of the PtCo/NGC catalyst were attributed to the formation of an intermetallic structure that alleviated the Pt oxidation and Co dissolution. The outstanding performance and stability qualify the ordered intermetallic PtCo/NGC to be a promising cathode catalyst for the commercialization of fuel cells.

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Jung, Won Suk, Lee, Woong Hee, Oh, Hyung-Suk, Popov, Branko N.. 2020-08-12. Highly stable and ordered intermetallic PtCo alloy catalyst supported on graphitized carbon containing Co@CN for oxygen reduction reaction. https://doi.org/10.1039/d0ta05182a

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