Au/WO3 nanocomposite based photocatalyst for enhanced solar photocatalytic activity

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2023-03, Vol.437, p.114427, Article 114427
• Main Authors: Desseigne, Margaux, Madigou, Véronique, Coulet, Marie-Vanessa, Heintz, Olivier, Chevallier, Virginie, Arab, Madjid
• Format: Article
• Language: English
• Subjects: Au/WO3 nanocomposite; Catalysis; Chemical Sciences; Dyes degradation; Material chemistry; Photocatalyst; Solar photocatalysis
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2022.114427

[Display omitted] •Photosensitive and electrical properties enhancement of WO3 by loading gold nanoparticles on the particles’ surface.•Gold nanoparticles loaded on tungsten trioxide platelet-like by a simple impregnation-deposition technique at room temperature.•High improvement of charge carriers’ lifetime of the oxide by gold nanoparticles deposition with a mean size of 7 nm.•Complete degradation in only 90 min of a cationic dye in aqueous media under solar light in presence of Au/WO3 nanocomposite.•Proposition of a methylene blue mineralization pathway in our photocatalytic degradation conditions by LC-MS analyses. Gold nanoparticles (AuNPs) were loaded on tungsten trioxide (WO3) platelet-like support by a simple impregnation deposition technique at room temperature. Textural, structural and electrical properties were characterized for the as prepared material. The SEM/TEM investigations revealed that formed AuNPs possess a mean diameter of 7 nm and a preferential deposition on the (0 2 0) planes of the orthorhombic WO3 structure. The photodegradation efficiency was evaluated under solar light irradiation using dye pollutant solutions such as rhodamine B (RhB), methylene blue (MB) and methyl orange (MO). According to the affinity between the organic pollutant and the catalyst support, the adsorption/photocatalysis yield and the degradation pathway differ. It was observed that MB created strong electrostatic bonds with the catalyst support while RhB and MO did not adsorb on Au/WO3 hybrid sample. Photocatalytic tests revealed a high performance of Au/WO3 photocatalyst with a complete degradation in 90 min for a cationic dye mainly due to the oxidation by the hydroxyl reactive oxidant species. LC-MS analyses confirmed a higher decomposition with gold compared to bare WO3 on the MB pollutant and results permit to propose a degradation pathway.