Preparation of a Graphitized-Carbon-Supported PtNi Octahedral Catalyst and Application in a Proton-Exchange Membrane Fuel Cell.

In this work, PtNi/GC octahedral nanocrystal catalysts are prepared using graphitized carbon (GC) to solve the problems of cathode catalysts in catalytic performance and proton-exchange membrane fuel cell application. The as-prepared supported catalysts exhibit well-crystallized octahedral morphologies and graphite layer structures with high corrosion resistance. Their mass activities and specific activities are 5 and 7 times higher than those of the commercial Pt/C. The sample with the best performance shows the cell voltage at 1000 mA cm-2 of 0.672 V and maximum power density of 817.6 mW cm-2 in the single-cell test, which are increased by 23 mV and 13.2 mW cm-2 compared to the control. Especially after a high potential test, the above two parameters of this sample are reduced by only 5.6 and 8.4%, which are significantly lower than the attenuation of the control fabricated using Vulcan XC-72 carbon black. The work reveals that the GC-supported PtNi octahedral catalysts can give better consideration to the improvement of electrochemical and single-cell performances.