Sunlight-Triggered Dye Degradation and Antibacterial Activity of Graphene-Iron Oxide-Titanium Dioxide Heterostructure...

Iron oxide (Fe₂O₃)-titanium dioxide (TiO₂) heterostructure nanocomposite has been used for contaminant decomposition and antibacterial application. However, both the photogenerated electrons and holes of TiO₂ may transfer to Fe₂O₃ due to straddling band alignment in type-I heterostructure, which is not helpful to more efficiently inhibit the electron-hole recombination. In this paper graphene-Fe₂O₃-TiO₂ (GFT) heterostructure nanocomposites (NCs) were fabricated to facilitate the separation of photo-induced electrons and holes according to their staggered energy level, further improve dye degradation efficiency and antibacterial activity. GFT NCs were fabricated through a simple hydrothermal method. X-ray diffraction patterns and transmission electron microscopy images indicated that Fe₂O₃ and TiO₂ were successfully loaded on graphene. UV-Vis spectra showed that GFT NCs had higher absorption against sunlight. Under simulated sunlight irradiation, GFT NCs could effectively degraded dyes and inhibit bacterial growth.