Key Properties and Parameters of Pd/CeO2Passive NO xAdsorbers

Abstract

In this paper, a series of Pd/CeO2catalysts prepared by different synthesis routes and showing different morphological and textural properties have been investigated for passive NOxadsorption (PNA) applications. The results obtained by NOxadsorption/desorption tests demonstrated that NOxstorage capacity and NOxstorage efficiency of Pd/CeO2materials depend strictly on their surface area, whereas the morphology of the support and the Pd deposition method do not seem to play a key role. In contrast, the Pd deposition method does impact the dynamics of NOxdesorption by affecting the amount of NOxdesorbed at different temperatures. This seems to be connected to Pd-Ce interactions at the nanoscale that favor NOxdesorption at higher temperatures suitable for PNA application. These findings are relevant in designing and optimizing the properties of Pd/CeO2materials for their function as passive NOxadsorbers.