Abstract:This study presents the preparation and application of nano γ-Fe2O3/TiO2 nanotube magnetic heterojunction photocatalysts (MHPs) for photodegradation of methylene blue under visible light irradiation. The morphology, microstructure, magnetic properties, and photocatalytic activity of γ-Fe2O3/TiO2 (NT) MHPs were studied. The results showed that the MHPs were provided with highly ordered TiO2 (titania) nanotube arrays (55 nm diameter and 10 nm wall thickness) and nano γ-Fe2O3 (maghemite) particle (approximately 15 nm) co-deposition. The MHPs exhibited a superparamagnetic behavior of γ-Fe2O3/TiO2 (NT) MHPs resulting from the small size of γ-Fe2O3 particles. The photocatalytic activity of γ-Fe2O3/TiO2 (NT) MHPs was greater than that of Fe3O4/TiO2 (NT) MHPs or pure TiO2 (NT) under visible light irradiation. The interaction between γ-Fe2O3 and TiO2 improved charge separation and extended TiO2 response into the visible region. Moreover, the formed heterojunction between γ-Fe2O3 and TiO2 could further prevent the recombination between photoelectrons and holes.