Solvothermal method coupled with thermal decomposition for synthesis of non-stoichiometric BiO1.18I0.64 with excellent photocatalytic activity

摘要

A series of non-stoichiometric BiOxI3-2x photocatalysts were successfully prepared by a solvothermal method combined with thermal decomposition. Among them, BiO1.18I0.64 exhibited the highest photocatalytic activity. The degradation rate of aniline (50 mg L-1) over the photocatalyst (1 g L-1) was about 92.5% after 3 h of white LED lamp irradiation. Density functional theory calculations demonstrated that a much faster velocity of relative movement between electron and hole, as well as an apparently enhanced internal electric field in BiO1.18I0.64 greatly facilitated separation of photogenerated electron-hole pairs, which significantly improved its photocatalytic activity. In addition, I-vacancies in BiO1.18I0.64 could play an important role in capturing holes and thereby inhibiting the recombination of photoinduced electron-hole pairs. It further accounted for the obviously enhanced photocatalytic activity of BiO1.18I0.64.