Surface Modification of Magnetic TiO2 Core-Shell with Doped Cerium for Enhancement of Photocatalytic Performance

Abstract

The core-shell structure of Ce-doped TiO 2 @SiO 2 @(Ni-Cu-Zn) ferrite noted of CTSF as composite nanoparticles (NPs) was synthesized using a modified sol-gel method. The physicochemical properties of as-prepared products were characterized completely by X-ray diffraction (XRD), Brunauer-Emmit-Teller (BET), X-ray photoelectron spectroscopy (XPS) and superconducting quantum interference device (SQUID), serially. Meanwhile, assessment of the photocataly s tic activity of catalyst was performed by ultraviolet-visible spectrometry (UV-vis). The results of the study show that the anatase phase related to the TiO 2 structure was constructed on the outer shell coating of composite NPs. However, the second phase associated with the Ce structure was not easy to be detected on the XRD pattern, confirming that the doping Ce had been incorporated into the TiO 2 crystal structure. The mesoporous structure of Ce-doped TiO 2 layers was demonstrated by the type IV isotherm and H3 type hysteresis loop. The homogenous pore size was generated with the specific surface area up to 111.916 m 2 /g and 0.241 cc/g of pore volume. The stoichiometry of the chemical composition formed with fewer defects on the surface of TiO 2 layers was exhibited by the symmetry curve of Ti 2p 3/2 and Ti 2p 1/2 peaks of XPS spectra. Meanwhile, the redox couple corresponding to Ce 3+ /Ce 4+ was incorporated inside the thin TiO 2 coating. Furthermore, the catalyst magnetic NPs can be also separated by using an external magnetic field from the reaction system. The product performance associated with the degradation efficiency was achieved to be 50 % in the aqueous solution of methylene blue (MB)