Enhancing the catalytic performance of Pt/C catalysts using steam-etched carbon blacks as a catalyst support

XC72 carbon blacks were treated using a steam-etching technique. Pt catalysts using steam-etched carbon blacks (SECBs) as supports were developed for oxygen reduction reactions in polymer electrolyte fuel cells (PEFCs). The use of the steam-etched carbon blacks as a catalyst support can improve the dispersion uniformity of Pt nanoparticles on the surface of the support and can decrease the Pt particle size, as indicated by transmission electron microscopy (TEM) data. The overall catalytic performance of the catalysts using SECBs was better than that of the catalysts using non-SECBs. The mass activity of the Pt catalysts using SECBs etched for 1 h had the best catalytic performance for both the catalysts using SECBs and those using non-SECBs. In addition, the electrochemically active surface area of the Pt/SECBs significantly increased after etching. TEM results revealed that the center of the carbon black was more easily etched than the surface.

(a) Cyclic voltammograms in 0.1 M HClO4 purged with N2 at room temperature at a sweep rate of 20 mV s−1. (b) Polarization curves for ORR (on a rotating disk electrode, 1600 rpm, in 0.1 M HClO4 purged with O2 at room temperature at a sweep rate of 20 mV s−1).Figure optionsDownload as PowerPoint slideResearch highlights
► The steam-etched XC72 carbon black was used as a catalyst support for oxygen reduction reaction.
► The mass activity of the etched samples was better than that of the unetched samples and a commercial E-TEK catalyst with the same Pt loading.
► The electrochemically active surface area of the samples was also increased after etching.