Morphological effect of ceria-supported platinum catalyst on low-temperature ethylene oxidation

Three types of Pt/CeO 2 catalysts with different support morphologies (rod (CeO 2 -R), cube (CeO 2 -C), and octahedron (CeO 2 -O) were synthesized especially for catalytically oxidizing C 2 H 4 at low temperatures. The as-prepared catalysts exhibited strong shape-dependent catalytic activity in the order of Pt/CeO 2 -O > Pt/CeO 2 -C > Pt/CeO 2 -R. Such unique performance is mainly attributed to the different steps of C 2 H 4 oxidation associated with the variation of oxygen species activated by Pt/CeO 2 catalysts. Among the three catalysts, Pt/CeO 2 -O had the least issue with the accumulation of intermediate species and consequently performed the highest low-temperature C 2 H 4 catalytic oxidation activity. Moreover, the negative impact of water condensation on the catalyst can be readily eliminated by refreshing the catalyst with N 2 purging. Overall, this work led to a novel catalytic system for efficient low-temperature ethylene oxidation and a better understanding of the catalytic mechanism, thus benefiting the preservation of fruits and vegetables as one of the applications.