CNR ExploRA

Articolo in rivista, 2021, ENG, 10.1021/acsami.1c09921

Tailored Co3O4-based nanosystems: towards novel photocatalysts for air purification

Fragoso J.; Barreca D.; Bigiani L.; Sada C.; Lebedev O.I.; Modin E.; Pavlovic I.; Sánchez L.; Maccato C.

1,7,8: Department of Inorganic Chemistry and Chemical Engineering, Córdoba University, 14071 Córdoba, Spain 2: CNR-ICMATE and INSTM, Department of Chemical Sciences, Padova University, 35131 Padova, Italy 3,9: Department of Chemical Sciences, Padova University and INSTM, 35131 Padova, Italy 4: Department of Physics and Astronomy, Padova University and INSTM, 35131 Padova, Italy 5: Laboratoire CRISMAT, 14050 Caen, France 6: CIC nanoGUNE BRTA, 20018 Donostia-San Sebastian, Spain

The adverse effects of NOx (NO + NO2) gases on the environment and human health have triggered the development of sustainable photocatalysts for their efficient removal (De-NOx). In this regard, the present work focuses on supported Co3O4-based nanomaterials fabricated via chemical vapor deposition (CVD), assessed for the first time as photocatalysts for sunlight-activated NO oxidation. A proofof- principle investigation on the possibility of tailoring material performances by heterostructure formation is explored through deposition of SnO2 or Fe2O3 onto Co3O4 by radio frequency (RF) sputtering. A comprehensive characterization by complementary analytical tools evidences the formation of high-purity columnar Co3O4 arrays with faceted pyramidal tips, conformally covered by very thin SnO2 and Fe2O3 overlayers. Photocatalytic functional tests highlight an appreciable activity for bare Co3O4 systems, accompanied by a high selectivity in NOx conversion to harmless nitrate species. A preliminary evaluation of De-NOx performances for functionalized systems revealed a direct dependence of the system behavior on the chemical composition, SnO2/Fe2O3 overlayer morphology, and charge transfer events between the single oxide constituents. Taken together, the present results can provide valuable guidelines for the eventual implementation of improved photocatalysts for air purification.

ACS applied materials & interfaces (Print) 13 , pp. 44520–44530