Synthesis of Fe₃O₄/C/TiO₂Magnetic Photocatalyst via Vapor Phase Hydrolysis

Abstract

A core/multi-shell-structured Fe 3 O 4 /C/TiO 2 magnetic photocatalyst is prepared via vapor phase hydrolysis process. The as-synthesized core/multi-shell-structured composite is characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high-resolution electron microscopy (HRTEM), N 2 adsorption-desorption isotherm analyses, vibrating sample magnetometer (VSM), and ultraviolet-visible (UV-Vis) absorption spectroscopy. TEM and HRTEM show that well-crystallized anatase TiO 2 nanocrystals are immobilized on the surface of as-prepared Fe 3 O 4 /C microspheres with dimensions around 200 nm. N 2 adsorption-desorption isotherm analysis shows that the obtained photocatalyst exists disorderedly mesoporous structure. The photocatalytic efficiency of the catalyst in degradation of methylene blue is evaluated, and the Fe 3 O 4 /C/TiO 2 photocatalyst with low TiO 2 content (37%) has a relatively higher activity than commercial anatase TiO 2 . The intermediate carbon layer avoids the photodissolution of Fe 3 O 4 effectively, and the recycling property is largely improved due to the existence of magnetic Fe 3 O 4 core.