Influence of Chromium Carbide-Derived Carbon Support and Ceria Nanocrystals on Pt–CeO₂/C Catalysts for Fuel Cell Applications

Abstract

The influence of different synthesis parameters on CeO2 and Pt nanoparticle (NP) deposition on Ketjenblack carbon (C(KB)) was examined. The Pt NP diameter (3.1–4.1 nm) was not influenced by CeO2 synthesis parameters. The CeO2 NPs synthesized using ultrasound sonication contribute to a better durability of the Pt-CeO2/C against CO poisoning. In contrast, CeO2 synthesized using the microwave heating method contributes to better methanol oxidation reaction (MOR) activity at low potential. Synthesis parameters of CeO2 and Pt NPs developed for the C(KB)-based catalysts were applied for C(Cr3C2)-based catalysts. The Pt NP diameter of C(Cr3C2)-based catalysts was slightly higher (7.2 nm) as some Pt NPs were agglomerated. The C(Cr3C2) support facilitates the MOR and CO stripping, especially in the case of the Pt/C on C(Cr3C2) support. The MOR activity at 0.85 V of Pt/C on the C(Cr3C2) support is as good as the MOR activity for the best Pt-CeO2/C on the C(KB) support. The C(Cr3C2) support also improves the CO removal from the Pt surface. All the synthesized catalysts had better MOR activity than the commercial Pt/C(Vulcan) catalyst. The oxygen reduction reaction activity of Pt-CeO2/C catalysts with higher CeO2 content synthesized with the microwave heating method was very good.