UV Photovoltaic detector based on Bi doped TiO2 Fabricated by Pulse Laser Deposition

Pure and doped TiO2 with Bi films are obtained by pulse laser deposition technique at RT under vacume 10-3mbar, and the influence of Bi content on the photocvoltaic properties of TiO2 hetrojunctions is studied. All the films display photovoltaic in the near visible region. A broad double peaks are observed around ?= 300nm for pure TiO2 at RT in the spectral response of the photocurrent, which corresponds approximately to the absorption edge and this peak shift to higher wavelength (600 nm) when Bi content increase by 7% then decrease by 9%. The result is confirmed with the decreasing of the energy gap in optical properties. Also, the increasing is due to an increase in the amount of Bi content, and shifted to 400nm when annealed at 523 K as results of decreasing the energy gap.