Photocatalytic Degradation of Paracetamol under Simulated Sunlight by Four TiO2 Commercial Powders: An Insight into the Performance of Two Sub-Micrometric Anatase and Rutile Powders and a Nanometric Brookite Powder

The photocatalytic degradation of the emerging contaminant paracetamol in aqueous solution has been studied under 1 SUN (~1000 W m−2) presence four commercial TiO2 powders, namely sub-micrometric anatase and rutile, nanometric brookite P25 (the popular anatase/rutile mixture used as a benchmark most papers). rutile powder showed low activity, whereas, interestingly, powders outperformed terms total conversion to carboxylic acids, which, according literature, are final products its degradation. To explain such results, physicochemical properties were by applying multi-technique approach. Among usually affecting performance TiO2, some surface impurities likely deriving from K3PO4 (used crystallization agent) was found significantly affect percentage obtained with powder. confirm role phosphate, sample anatase, lab synthesis procedure having “clean” surface, control, though characterized particles higher area. less active than but it more after impregnation K3PO4. Conversely, Cl at did not sizably (overall poor) activity remarkable ascribed combination several properties, including band structure nanoparticles size.