Gold over Ceria–Titania Mixed Oxides: Solar Light Induced Catalytic Activity for Nitrophenol Reduction

The present study shed light on synthesis, characterization and solar light induced catalytic activity studies for reduction of 4-nitrophenol by CeO 2 and nano gold catalysts supported over CeO 2 and CeO 2 –TiO 2 (1:1 mol ratio). The support systems were prepared by simple precipitation technique and the gold supported samples were synthesized using modified deposition–precipitation with urea method. The physicochemical characterization was performed by XRD, UV–Vis DRS, BET surface area, ICP-AES, TEM and XPS techniques. The catalytic performance of the synthesized catalysts were measured spectrophotometrically by engaging them for the reduction of 4-nitrophenol to 4-aminophenol in presence of NaBH 4 serving as a hydrogen source. Au/CeO 2 –TiO 2 has been found to be a very effective catalyst showing ~100 % conversion in short reaction time. The catalytic activity of the Au/CeO 2 –TiO 2 showed no significant difference even after recycling the catalyst for four times indicating a promising potential for industrial application. Graphical Abstract