Promoted catalytic activity of CO oxidation at low temperatures by tuning ZnO morphology for optimized CuO/ZnO catalysts

Abstract

Catalytic oxidation of CO is an effective route to eliminate the pollution of automobile exhaust. Tuning the fraction of exposed polar and non-polar crystal facets in ZnO provides an effective strategy to tailor metal-oxide interfacial active sites. Herein, the morphology of ZnO support was tuned to alter the fraction of exposed (002) polar/(100), (101) non-polar facets. ZnO nanodisks and nanorods were prepared, followed by deposition of ∼3.1 ± 0.9 nm CuO nanoparticles. The impact of the ZnO morphology upon CuO deposition and catalytic activity towards CO oxidation were investigated. The CuO/ZnO derived from ZnO nanodisks (NDs) with the most exposed (002) polar plane exhibited more than 2 folds higher catalytic activity at 150 °C than that over CuO/ZnO with commercial ZnO support (CuO/ZnO-C), highlighting the morphology influence of ZnO. For its enhanced catalytic activity and cyclic stability, the CuO/ZnO-NDs could be a promising catalyst for CO oxidation.