Efficient photocatalytic removal of phthalates easily implemented over a bi-functional {001}TiO2 surface

It is stubborn to remove the lowly concentrated phthalic acid esters (PAEs) that usually coexist with other highly concentrated but low-toxic pollutants in municipal sewage. Herein, we report a novel strategy for completely removing the PAEs over a bi-functional {001}TiO 2 surface (with highly exposed {001} facet), which not only serve as functional sites to specifically adsorb the target PAEs pollutants, but also contribute to an enhanced oxidation ability. The adsorption behavior of PAEs on {001}TiO 2 is analyzed deeply through kinetic experiments combining with in situ ATR-FTIR spectroscopy and theoretical calculations. The results reveal that the adsorption capacities of PAEs on {001}TiO 2 are about 4–5 times higher than that on TiO 2 , both of which follow the pseudo-second-order and Langmuir model. This is mainly attributed to the interfacial Lewis Acid-Base Pair between {001} facet Ti 5c sites and C O of PAEs. Benefitting from the specific adsorption capability toward target pollutant and enhanced oxidation ability of {001} facets, nearly 100% of DMP or DEP in simulated wastewater can be eliminated by {001}TiO 2 within 2 h illumination, and the relevant degradation rate constants ( k ) (3.67 h −1 for DMP and 2.19 h −1 for DEP) are 5.73 and 3.08 folds higher than that of pure TiO 2 , respectively. In the application of municipal wastewater , nearly 76% of DMP and 85% DEP can be eliminated by {001}TiO 2 within 2 h illumination, which are nearly 3–6 fold higher than that of pure TiO 2 .