Heterostructured CeO2-M (M = Co, Cu, Mn, Fe, Ni) Oxide Nanocatalysts for the Visible-Light Photooxidation of Pinene to Aroma Oxygenates.

ABSTRACT: Herein, we report the enhanced photocatalytic activity of heterostructured CeO2 nanocatalysts interfaced with Cu, Co, Ni, Mn, and Fe metal oxides. The CeO2 catalysts exhibited an enhanced red shift in the visible-light response compared to CeO2. This improved absorption range effectively suppressed electron (e-)/hole (+h) recombination by forming localized energy bands associated with defect oxygen vacancies (V o) induced by the Mn+ ions incorporated in CeO2. Under visible-light irradiation, CeO2 catalysts are active for ?-pinene oxidation to the aroma oxygenates, pinene oxide, verbenol, and verbenone. Both Fe2O3-CeO2 and NiO-CeO2 gave the highest pinene conversions of 71.3 and 53.1%, respectively, with corresponding pinene oxide selectivities of 57.3 and 58.2%. The enhanced photocatalytic performance of the heterostructured CeO2 catalysts compared to CeO2 is attributed to their enhanced visible-light absorption range and efficient suppression of e-/+h recombination. The Fe2O3-CeO2 catalyst was highly recyclable and did not show any significant loss of its photoactivity.

SUBMITTER: Mavuso MA 

PROVIDER: S-EPMC7203698 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature