Ozone activated Ag/CeO2 catalysts for soot combustion: The surface and structural influences

Abstract

In this work, O3 activation was performed at 200 °C over two types of Ag/CeO2 catalysts with nanocube- and nanorod-like morphologies, respectively. The O3-indcued surface Ox− species (“Ox− injection”) accelerated soot combustion over both catalysts temporarily. In contrast, the depletion of CeO2 surface oxygen vacancies (Ce3+-VO-s) caused by ozonization conferred to long-term activation. Specifically, the ozonized nanocubic Ag/CeO2 with low initial Ce3+ content not only benefited more from the “Ox− injection”, but also exhibited good redox stability and high practical potential. Therefore, the combination of this catalyst with O3 activation may result in efficient soot elimination in the particulate filters of vehicles.