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 CeO _2 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 CeO _2 synthesis parameters. The CeO _2 NPs synthesized using ultrasound sonication contribute to a better durability of the Pt–CeO _2 /C against CO poisoning. In contrast, CeO _2 synthesized using the microwave heating method contributes to better methanol oxidation reaction (MOR) activity at low electrode potential. Synthesis parameters of CeO _2 and Pt NPs developed for the C(KB)-based catalysts were applied for C(Cr _3 C _2 )-based catalysts. The Pt NP diameter of C(Cr _3 C _2 )-based catalysts was slightly higher (7.2 nm) as some Pt NPs were agglomerated. The C(Cr _3 C _2 ) support facilitates the MOR and CO stripping, especially in the case of the Pt/C on C(Cr _3 C _2 ) support. The MOR activity at 0.85 V of Pt NPs on the C(Cr _3 C _2 ) support is as good as the MOR activity for the best Pt–CeO _2 on the C(KB) support. The C(Cr _3 C _2 ) 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–CeO _2 /C catalysts with higher CeO _2 content synthesized with the microwave heating method was very good.

Keywords

• methanol oxidation reaction
• oxygen reduction reaction
• ethylene glycol reduction method
• chromium carbide-derived carbon
• platinum-ceria catalysts
• PEMFC