A convenient approach of MIP/Co-TiO nanocomposites with highly enhanced photocatalytic activity and selectivity under visible light irradiation

Molecular imprinted polymer coated Co-doped TiO 2 nanocomposites (MIP/Co-TiO 2 nanocomposites) were successfully synthesized by a surface molecular imprinting technique using rhodamine B (RhB) as the template molecule and p -phenylenediamine as the functional monomer. The surface structure and properties of the nanocomposite catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption/desorption measurements (BET) and UV-vis diffuse reflectance spectra (UV-vis DRS). The preferentially selected degradation and activity of imprinted photocatalysts were evaluated by degradation of the template molecule RhB relative to rhodamine 6G (Rh6G) under visible light irradiation. Compared with the non-imprinted Co-doped TiO 2 nanocomposites (NIP/Co-TiO 2 nanocomposites), the MIP/Co-TiO 2 nanocomposites exhibited higher photo-degradation rate for RhB and also showed enhanced selective activity for RhB. The k value for the photodegradation of RhB over MIP/Co-TiO 2 nanocomposites was 0.03606 min −1 , being 215.7% that of RhB over NIP/Co-TiO 2 nanocomposites (0.01672 min −1 ) and 337.3% that of RhB over Co-TiO 2 nanoparticles (0.01069 min −1 ). The k value for the photodegradation of RhB over MIP/Co-TiO 2 nanocomposites was 0.03606 min −1 , being 150.5% that of Rh6G over MIP/Co-TiO 2 nanocomposites (0.02396 min −1 ). Moreover, the MIP/Co-TiO 2 nanocomposites exhibited high stability and reusability. MIP/Co-TiO 2 nanocomposites were synthesized. Their mechanisms of preferable photocatalytic activity and good selectivity for target contaminants were identified and discussed.