Catalyst Poisoning Property of Sulfonimide Acid Ionomer on Pt (111) Surface

A thin film of a novel ionomer, NBC4, which has two sulfonimide acid groups in its side chain ended with a hydrophobic group, instead of sulfonic acid groups, was formed on a Pt (111) surface and its catalyst poisoning property was compared with that of Nafion, which has sulfonic acid groups. For NBC4, anionic poisoning is weaker and oxygen reduction reaction activity is higher by ca. 30% below 0.86 V vs the reversible hydrogen electrode than for Nafion.