Au/CeO2 Photocatalyst for the Selective Oxidation of Aromatic Alcohols in Water under UV, Visible and Solar Irradiation

Abstract

Au nanoparticles supported on CeO2 have been prepared and investigated as photocatalysts for the photocatalytic selective oxidation of benzyl alcohol and 4-methoxybenzyl alcohol to the correspondent benzaldehydes, in aqueous suspensions and room conditions under UV, visible and natural solar light irradiation. Au nanoparticles have been supported by impregnation (1 and 3 wt.%) on two types of CeO2 (i.e., a commercial one and a home prepared oxide obtained in the presence of NaOH as precipitation agent). The Au impregnated samples showed strong visible radiation absorption at 565–570 nm associated to localized surface plasmon resonance (LSPR). The bare CeO2 samples are activated by UV light and resulted virtually inactive under visible irradiation, whereas the presence of Au improved both the conversion of the alcohols and the selectivity of the reaction towards the aldehyde, giving rise to good results, particularly under visible and natural solar light irradiation. The activity of the materials increased by increasing the Au content.

Integrating TEMPO into a Metal–Organic Framework for Cooperative Photocatalysis: Selective Aerobic Oxidation of Sulfides

“…The selective aerobic oxidation of organic molecules by photocatalysis is uniquely positioned to demonstrate the rational design of a system. − As a proof of concept, the selective oxidation of organic sulfides to sulfoxides was selected as the model reaction. Sulfoxides are essential in manufacturing physiologically active compounds, therapeutic molecules, and natural products .…”

CeO2-rGO Composites for Photocatalytic H2 Evolution by Glycerol Photoreforming

“…In the gold-containing samples, it is possible to distinguish the signal at 556 nm due to the plasmon of the metal. According to the surface plasmon resonance (SPR) effect theory, due to the lower dielectric constant of CeO 2 compared to TiO 2 , the position of this signal is shifted to higher wavelengths with respect to the TiO 2 -based samples [ 20 , 21 , 22 ]. The figure in panel (b) illustrates the TAUC plots for the previously discussed samples.…”

Cds Nanoparticles Decorated 1D Ceo₂ Nanorods for Enhanced Photocatalytic Desulfurization Performance

“…CeO2 is an important rare earth oxide semiconductor material, which is commonly used as a photocatalyst for pollutant degradation and energy conversion. However, CeO2 is a wide band gap semiconductor, which usually responds in the ultraviolet region, and the ultraviolet light only accounts for 5% of the sunlight, which greatly hinders its application [16][17][18]. Therefore, the heterojunction of CeO2 and another narrow band gap semiconductor is expected to improve the photocatalytic performance.…”