Suppressing NOM access to controlled porous TiO2 particles enhances the decomposition of target water contaminants

Preferential oxidation of target chemicals of concern has been a challenging issue in TiO2 photocatalysis, considering typical source water contains low concentrations of highly toxic substances along with high concentrations of less toxic naturally abundant organic matter (NOM). This study demonstrates simply controlling the porous structure of TiO2 can suppress the access of large size NOM to the TiO2 and thus improve the selective oxidation of small size target contaminants. Ibuprofen as a target contaminant was successfully decomposed even in the presence of humic acid as competing NOM. Selectivity enhancement mechanism was proposed, based on size exclusion principle. (C) 2013 Elsevier B.V. All rights reserved.