High performance ultraviolet detector based on TiO2/ZnO heterojunction

TiO2 nanowires array is synthesized on the FTO via hydrothermal method, which is modified with ZnO prepared by using the crystallization method. The fabricated ultraviolet detector based on TiO2/ZnO heterojunction possesses high photoelectric performance evaluated by the photo-to-dark current ratio, which has been demonstrated to reach 4 orders of magnitude. The separation of electron–hole pairs is facilitated by the built-in electric field in heterojunction, resulting in a large photocurrent as well as a high responsivity, which can attain 150 A/W. Compared with the pure TiO2 device, The red shift in both absorption spectrum and photo response provides a potential application for the TiO2/ZnO device.