Molecularly imprinted TiO2 hybridized magnetic Fe3O4 nanoparticles for selective photocatalytic degradation and removal of estrone

Abstract

As a widely used photocatalyst, titania (TiO₂) enjoys significant advantages; however, it faces the severe challenge of poor selectivity. And interestingly, molecular imprinting gains great popularity, owing to its desired recognition specificity. Herein, by using estrone as a template molecule, we prepared molecularly imprinted TiO₂ hybridized magnetic ferroferric oxide (Fe₃O₄) nanoparticles through a semi-covalent approach by a liquid phase deposition method, for selective photocatalytic degradation and removal of target estrone with the irradiation of UV light. The obtained Fe₃O₄@SiO₂@imprinted TiO₂ displayed high adsorption capacity, fast kinetics and high selectivity. In the presence of 10 times of coexisting nontarget compounds, the apparent rate constant, k_app, for photodegradation of target estrone over the hybridized nanoparticles, was about 6 times of that over net TiO₂. Also, excellent stability during long-time photocatalysis was exhibited. More importantly, the Fe₃O₄@imprinted TiO₂ provided potential application prospectives for photocatalytic removal of trace target organic pollutants in the presence of high-level pollutants.