Synthesis of Cu2O/graphene/rutile TiO2 nanorod ternary composites with enhanced photocatalytic activity

• A ternary composite of Cu2O/graphene/rutile TiO2 nanorods were successfully fabricated.
• Red shift and more absorption in the visible light region were observed for the ternary composites.
• Improved photocatalytic degradation was detected with the introduction of Cu2O and graphene.
• Both Cu2O and graphene played an important role to improve the photocatalytic activity of TiO2.

A ternary composite of Cu2O, graphene and rutile TiO2 nanorods was prepared using Cu(CH3COO)2·H2O, graphene oxide and TiCl4 as the starting materials and its enhanced photocatalytic performance was demonstrated. Graphene/TiO2 nanorod composites (GT) were obtained by a simple hydrothermal method and then, Cu2O was coupled onto the surface of graphene/rutile TiO2 to form Cu2O/graphene/rutile TiO2 nanorod (CGT) composites via a chemical bath deposition process. The as-prepared sample was characterized by X-ray diffraction (XRD), emission field scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), specific surface area analyzer (BET), Raman spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS). It is found that the introduction of graphene and Cu2O has little effect on the morphology of TiO2 nanorods with average dimensions of 140 nm (length) × 30 nm (diameter) (L/D ratio ≈5). A red shift of light absorption edge and more absorption in the visible light region were observed for the resulted ternary samples compared with TiO2 and graphene/TiO2 composites. The photocatalytic activity was evaluated by the photodegradation of methylene blue under visible light irradiation, which showed 2.8 times corresponding enhancement of the degradation efficiency for the ternary composites compared with TiO2. This work provides a new strategy to improve the visible light response of TiO2 and facilitate its application in environmental remediation.