Low temperature one-pot synthesis of Cu-doped ZnO/Al2O3 composite by a facile rout for rapid methyl orange degradation

•ZnO/Al2O3 composite modified by 2.5-10 wt% Cu were prepared using a set of wet chemical techniques.•Formed Al2O3/ZnO:Cu composite exhibited a supreme photocatalytic performance upon the degradation of MO.•The degradation rate of MO for optimum Cu-doped sample was almost 20 times the un-doped sample.

ZnO/Al2O3 composite modified by 2.5-10 wt% Cu were prepared using a set of wet chemical techniques (solvothermal, co-precipitation, ultrasonic and reflux) and characterized. All processes were done under the atmospheric condition and without any calcination step. The product was characterized by PXRD, FE-SEM, FT-IR and UV-Vis spectroscopy. The microscopy images clearly showed lamellar particles morphology in nano regime. X-ray diffraction studies revealed the wurtzite-type ZnO and γ-Al2O3 crystallinity. The Band gap varied from 3.20 eV for the un-doped Al2O3/ZnO sample to 2.18 eV for the Al2O3/ZnO:Cu with Cu content of 10%. Formed Al2O3/ZnO:Cu composite exhibited a supreme photocatalytic performance upon the degradation of methyl orange (MO) under visible-light irradiation. The optimum catalyst indicated completely remove of MO dye with the 15 mg L− 1 concentration from the water after 50 min photocatalytic reaction time, where for the optimum sample the removal efficiency was 77% after only 10 min reaction. Results showed that the inserting of Cu in composite improves the photocatalytic activity of ZnO under visible light. The degradation rate of MO for optimum Cu-doped sample was almost 20 times the un-doped sample.