Photocatalytic activity of boron-modified TiO2 under visible light: The effect of boron content, calcination temperature and TiO2 matrix

Our research examines the photoactivity under visible light (λ > 400 nm) and surface properties (BET surface area, UV–vis absorption properties, chemical composition and crystal structure) of boron-modified TiO2. B–TiO2 photocatalysts were prepared by surface impregnation procedure using boric acid triethyl ester (BATE) as a boron precursor. The photocatalytic activity of obtained powders in visible light was estimated by measuring the decomposition of phenol (0.21 mmol/dm3) in aqueous solution. The effect of boron content, calcination temperature and titanium dioxide source used during preparation procedure on photoactivity was investigated. The degradation of phenol indicated that the photoactivity under visible light strongly depended on preparation manner of B–TiO2 photocatalysts. The highest photoactivity was observed for the sample obtained by impregnation with 2 wt.% of BATE and calcinated at 400 °C. Phenol degradation rate, in the presence of these samples, equaled to 3.0 μmol dm−3 min−1. The mode of BATE binding to TiO2 surface is discussed.