0D/2D CeO2 quantum dots/NiO nanoplates supported ultralow content Pt catalyst for efficient oxidation of formaldehyde at room temperature
The development of cost-effective and high-powered catalysts to utterly decompose formaldehyde (HCHO) into CO2 and water at room temperature is an important challenge. In this work, we employed a hydrothermal method and followed by an impregnation-chemical reduction to successfully obtain a hybrid architecture of 0D/2D CeO2 quantum dots (QDs)/porous NiO hexagonal nanoplate supported ultralow content (0.08 wt%) Pt. 0D/2D CeO2/NiO composite supported Pt (Pt/NiCe4) with Ce/Ni molar ratio of 1:6 showed a HCHO removal efficiency of 87% in an hour, significantly higher than Pt/CeO2 (56%) and Pt/NiO (54%). The improved catalytic activity of Pt/NiCe4 is contributed by the unique morphology of CeO2 QDs deposited over NiO nanoplates leading to more exposed active sites and close contact of the components on a large scale, and large amount of active surface oxygen species stemmed from the insertion of Ni into CeO2 lattice and crucial role of Pt for the activation of O2 from the air. Moreover, the possible reaction mechanism for HCHO oxidation over Pt/NiCe4 was proposed based on the results of in situ diffused reflectance infrared Fourier transform spectroscopy studies and performance test. This study may provide some new enlightenment for constructing versatile catalysts in the application of indoor air purification.