A Core-Shell Fibrillar Electrocatalyst for the PEMFC Cathode By Microwave Accelerated Galvanic Displacement of Nickel with Platinum

Tuesday, 3 October 2017: 15:40
National Harbor 2 (Gaylord National Resort and Convention Center)
G. Ercolano, F. Farina, S. Cavaliere, J. Rozière, and D. J. Jones (CNRS - ICGM - AIME - University of Montpellier)
Currently Pt/Ni alloy [1] and de-alloyed [2] Pt/Ni nanoparticles, and the 3M nanostructured thin film catalyst of de-alloyed Pt/Ni films on whiskers [3] are some of the few to have met the DoE 2020 mass activity target of 0.44 A/mg Pt at 0.9 VIR free. The origin of the extraordinary activity shown by the Ni/Pt system is attributed to a delicate balance between a thin Pt shell and the sub-surface Ni content [1]. One approach to the preparation of highly active Ni/Pt electrocatalysts is by galvanic displacement of Ni from nanofibres with platinum [4]. We have recently found that is possible to reduce significantly the reaction time for Pt-Ni galvanic displacement by using a microwave-assisted procedure on Ni nanofibres, which leads to high mass activity catalysts (>0.5 A/mg Pt) in only 2 minutes. The shell thickness and density are controlled by extent of Ni/Pt displacement (Pt loading), itself controlled by the concentration of Pt ions in solution. By tuning the Pt content, Pt/Ni core/shell electrocatalysts were prepared that do not require electrochemical etching of surface Ni or de-alloying before utilisation. In addition the nickel core can be leached leaving chemically stable Pt4Ni thin tubular structure.


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[2] P. Strasser and S. Kühl, Nano Energy 26 1–12 (2016).

[3] M. K. Debe, R. T. Atanasoski and A. J. Steinbach, ECS Trans. 41 937–954 (2011).

[4] S. M. Alia, Y. S. Yan and B. S. Pivovar, Catal. Sci. Technol. 4 3589–3600 (2014).

Acknowledgement: This project has received funding from the Fuel Cells and Hydrogen 2 Joint Undertaking under grant agreement No 700127 INSPIRE. This Joint Undertaking receives support from the European Union’s Horizon 2020 research and innovation programme.