Z-scheme CuFe2O4–TiO2 nanocomposite microspheres for the photodegradation of methylene blue

Abstract

The design and synthesis of effective photocatalysts for photodegradation of persistent organic pollutants is of significant importance. Novel CuFe2O4 microspheres were successfully synthesized through a facile one-pot hydrothermal route. The composite CuFe2O4–TiO2 photocatalysts with a heterojunction were then fabricated through a simple mixing and heating method. The transmission electron microscopy (TEM) images revealed the clear hollow structure of the catalyst, and the TiO2 nanoparticles were attached tightly on the surface of the microspheres. Crystal structures and surface chemical composition of the photocatalysts were confirmed by powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. The band structure of the CuFe2O4–TiO2 photocatalyst was confirmed using Mott–Schottky measurements and UV–Vis absorption results. As expected, the CuFe2O4–TiO2 photocatalysts exhibited an enhanced photodegradation activity of methylene blue compared to bare CuFe2O4 and TiO2. A Z-scheme system was proposed and the efficient separation of photogenerated electron-hole pairs through the heterojunction resulted in the enhanced performance. This study provides an effective noble-metal-free and low-cost photocatalyst, and opens up a new synthesis strategy to construct other types of photocatalysts with morphology design.