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A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts

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Abstract

The morphology and size of Pt-based bimetallic alloys are known to determine their electrocatalytic performance in reactions relevant to fuel cells. Here, we report a general approach for preparing Pt-M (M = Fe, Co and Ni) bimetallic nano-branched structure (NBs) by a simple high temperature solution-phase synthesis. As-prepared Pt-M NBs show a polycrystalline structure and are rich in steps and kinks on the surface, which promote them favorable bifunctional catalytic properties in acidic electrolytes, specifically in terms of the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR). Specially, Pt-Co NBs/C catalyst shows 6.1 and 5.3 times higher in specific activity (SA) and mass activity (MA) for ORR than state-of-the-art commercial Pt/C catalysts, respectively. Moreover, it exhibits a loss of 4.0% in SA and 14.4% in MA after 10,000 cycles of accelerated durability tests (ADTs) compared with the initial activities. In addition, we also confirmed the superior MOR activity of Pt-Co NBs/C catalyst in acidic electrolytes. For Pt-M NBs with other alloying metals, the ORR and MOR activities are both higher than commercial catalysts and are in the sequence of Pt-Co/C > Pt-Fe/C > Pt-Ni/C > commercial Pt/C (or PtRu/C). The improved activities and durability can benefit from the morphological and compositional effects. This synthesis approach may be applied to develop bifunctional catalysts with enhanced ORR and MOR properties for future fuel cells designs.

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 51571072 and 51871078), Heilongjiang Science Foundation (No. E2018028), the China Scholarship Council, and the NSF MRSEC Program (DMR-14-19807).

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  1. Wenjuan Lei and Menggang Li contributed equally to this work.

Authors and Affiliations

  1. Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun, 130103, China

    Wenjuan Lei & Yongsheng Yu

  2. Ministry of Industry and Information Technology, Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China

    Wenjuan Lei, Menggang Li, Lin He, Xun Meng, Yongsheng Yu & Weiwei Yang

  3. Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China

    Zijie Mu

  4. Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA

    Wenjuan Lei & Frances M. Ross

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  1. Wenjuan Lei
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12274_2020_2666_MOESM1_ESM.pdf

A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts

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Lei, W., Li, M., He, L. et al. A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts. Nano Res. 13, 638–645 (2020). https://doi.org/10.1007/s12274-020-2666-3

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