Elucidation of the crucial catalytic effect of rubidium on oxygen reduction reaction

本研究旨在阐明在碱性溶液中Rb离子存在下金电极上增强氧还原反应(ORR)的机理。但是，电极的催化活性在很大程度上受存在的物质的影响，而不是Rb离子。用电感耦合等离子体光电子能谱和X射线光电子能谱对试剂进行了分析，结果表明试剂中含有微量的钍。在溶液中加入微量的铊离子进行ORR实验，结果表明催化剂的催化活性有了明显的提高。对电极表面的XPS分析表明，吸附的钍不仅改变了金电极表面的电子性质，而且改变了羟基在金电极表面的吸附量。

This study aimed to elucidate the mechanism of enhanced oxygen reduction reaction (ORR) at a gold electrode in the presence of rubidium ion in basic solutions. It was indicated, however, that the catalytic activity of the electrode largely influenced by the presence of substances other than rubidium ion. Chemical analyses using ICP and XPS revealed that a trace amount of thalium existed in the reagent of rubidium salts. The ORR experiment in the presence of tiny amount of thalium ion in the solution showed an appreciable improvement in the catalytic activity. XPS analysis of the electrode surface suggested that the adsorbed thalium can modify the electronic property as well as the adsorption amount of OH groups at the gold electrode surface.