Photoconducting Properties in Oxygen-Deficient Bi4Ti3O12
We investigated the influence of photoexcited nonequilibrium electrons in Bi4Ti3O12-d which contains a high density of oxygen vacancies. As increasing oxygen deficiency, the photocurrent undergoes a rapid enhancement, accompanied by a remarkable change of kinetics. In heavily oxygen deficient Bi4Ti3O12-d (d=0.45), we observed dispersive photoconductivity, a behavior resembles with persistent photoconductivity phenomena in some perovskites. We argue that oxygen vacancies acting as trapping centers for electrons are linked to dispersive diffusion in the perovskite blocks, which control carrier recombination.
Masaru Miyayama, Tadashi Takenaka, Masasuke Takata and Kazuo Shinozaki
M. Tada et al., "Photoconducting Properties in Oxygen-Deficient Bi4Ti3O12", Key Engineering Materials, Vol. 301, pp. 7-10, 2006