Superior methanol electrooxidation activity and CO tolerance of mesoporous helical nanospindle-like CeO2 modified Pt/C

Abstract

In an attempt to enhance the electrocatalytic activity and CO tolerance of ceria modified Pt/C electrodes, a novel structured ceria material has been developed. Left-handed helical CeO₂ nano-spindles with mesoporous structures were successfully synthesized through a template-free based precursor method on a large scale. By a microwave-assisted polyol synthesis process, the ceria modified Pt/C electrocatalysts were synthesized. The helical CeO₂ nanospindle based electrode Pt@Heli-CeO₂/C exhibits superior electrochemically active surface areas, and significantly enhanced methanol oxidation catalytic activity and CO antipoisoning activity, compared to Pt/C and a nano-octahedral CeO₂ modified electrode Pt@Octa-CeO₂/C. The experimental results show that Pt@Heli-CeO₂/C possesses 8.2 times and 3.2 times higher activity for methanol electrooxidation than Pt/C and Pt@Octa-CeO₂/C, respectively. This remarkable enhancement could be attributed to the reasons as follows: compared to octahedral CeO₂, the unique helical CeO₂ is more conductive with better electron transfer and can provide more active surface sites to strengthen the support–metal interactions based on an electronic transfer mechanism from CeO₂ to Pt, thus helical CeO₂ can promote better dispersion of the Pt(0) nanocrystallites and a high concentration of metallic Pt(0) in the composition.