TiO2-doped Fe3O4 nanoparticles as high-performance Fenton-like catalyst for dye decoloration

Fenton reaction based on Fe2+-H2O2 system has been widely applied in water remediation, but the obvious drawbacks largely hinder its practical uses. Alternatively, heterogeneous nanomaterials with proper surface modification could be used as Fenton-like catalysts. Surface doping of TiO2 could concentrate the pollutants surrounding the Fe3O4 catalyst, which might benefit the catalytic performance of Fe3O4. Herein, we reported that TiO2-doped Fe3O4 nanoparticles (NPs) could be used as high-performance Fenton-like catalyst for dye decoloration in near neutral environment, where the doping of TiO2 on Fe3O4 surface dramatically improved the catalytic activity of Fe3O4 in Fenton-like reaction. TiO2-doped Fe3O4 NPs catalyzed the decomposition of H2O2 to oxidize methylene blue without external energy supply, resulting in effective decoloration. TiO2-doped Fe3O4 NPs showed high catalytic activity under various pH values and even in the presence of radical scavenger. More catalysts and H2O2 would facilitate the decoloration. At higher temperature, the decoloration became faster and more effective. The implication to the environmental applications of TiO2-doped Fe3O4 NPs is discussed.