Support morphology effect on the selective oxidation of glycerol over AuPt/CeO2 catalysts

Abstract

We synthesized a series of CeO2 with controllable morphologies including nanocube (NC), nanorod (NR), and nanopolyhedron (NP), enclosed by different facets, and then explored the support morphology effect on catalytic properties of Au1Pt3 catalysts in glycerol oxidation. As expected, the series of Au1Pt3/CeO2 catalysts exhibit a conspicuous support facet-dependent catalytic performance especially for the catalytic activity. Specifically, the TOF ranks in the order that Au1Pt3/NC (937.8 h−1) > Au1Pt3/NR (713.1 h−1) > Au1Pt3/NP (491.7 h−1). Among three catalysts, Au1Pt3/NC exhibits the most notable interaction strength due to the highest oxidizing capability of Ce6c–O2c sites on NC (1 0 0), confirmed by in situ CO FT-IR. In this case, Pt0 species are more easily oxidized to Pt2+. The strong metal–support interaction promotes the activation ability of oxygen, resulting in the generation of more reactive oxygen species including O2−, O22−, and O−, among which O2− is proved to be the most favorable species.