Interface engineering of Bi2O3/Ag/TiO2 nanotubes heterojunction photodetector for UV imaging and optical communication

Large-scale Bi2O3/Ag/TiO2 nanotubes (BAT NTs) were successfully synthesized using ZnO nanorods template through the facile solution process at room temperature. Highly ordered BAT NTs with an average diameter of approximately 300 nm were arranged hierarchically on the overall ITO substrate. In addition, a self-powered UV photodetector (UVPD) based on BAT NTs was assembled and the photoresponse characteristics were investigated under a wide range of UV light intensity. The BAT NTs UVPD exhibits satisfactory UV photodetection perfor-mance with detectivity of 1.55 x 1010 Jones and on/off ratio exceeding 103, associated with a fast response speed of 25 ms, which is ascribed to the efficient carrier transport inspired by the 1D structure and energy band structure. In addition, BAT NTs UVPD also features excellent environmental stability and long cycling stability. Benefitting from the desirable properties, the BAT NTs UVPD achieves high-resolution imaging results with "UV" pattern as a single pixel unit and performs accurate UV optical communication as a signal receiver at zero bias. Eventually, the detailed self-powered UV detection mechanism for BAT NTs UVPD was illustrated.