Promotion of hydrogen uptake in cerium dioxide

Abstract

The interaction of hydrogen with ceria and iridium-ceria catalysts was studied at isothermal conditions and by temperature-programmed methods. Independent of the final temperature of reduction, hydrogen uptake during TPR was promoted by the presence of iridium in iridium-ceria catalysts. Partially reduced ceria was capable of storing hydrogen. The hydrogen storage ability increased with the reduction temperature of the ceria. It was also promoted by the presence of iridium. Various hypotheses, including the formation of Ir-Ce clusters at low temperature and hydrogen spillover, are considered to explain the observations.