Synthesis of Br-doped TiO hollow spheres with enhanced photocatalytic activity.

Wang, Qianqian; Zhu, Shengli; Liang, Yanqin; Cui, Zhenduo; Yang, Xianjin; Liang, Chunyong; Inoue, Akihisa

The Br-doped hollow TiO photocatalysts were prepared by a simple hydrothermal process on the carbon sphere template following with calcination at 400 °C. The structure and properties of photocatalysts were characterized by X-ray diffraction, Raman spectrum, scanning electron microscope, transmission electron microscopy, N desorption-adsorption, UV-Vis spectroscopy, and X-ray photoelectron spectroscopy. The TiO hollow spheres are in diameter of 500 nm with shell thickness of 50 nm. The shell is composed of small anatase nanoparticles with size of about 10 nm. The TiO hollow spheres exhibit high crystalline and high surface area of 89.208 m/g. With increasing content of Br doping, the band gap of TiO hollow spheres decreased from 2.85 to 1.75 eV. The formation of impurity band in the band gap would narrow the band gap and result in the red shift of absorption edge from 395 to 517 nm, which further enhances the photocatalytic activity. The appropriate Br doping improves the photocatlytic activity significantly. The TiO hollow spheres with 1.55% Br doping (0.5Br-TiO) exhibit the highest photocatalytic activity under full light. More than 98% of RhB, MO, and MB can be photodegraded using 0.5Br-TiO with concentration of 10 mg/L in 40, 30, and 30 min, respectively. The degradation rate of Br-doped photocatalysts was 40% faster than undoped ones.

BROMIDES; CATALYTIC doping; TITANIUM oxides; PHOTOCATALYSIS; HYDROTHERMAL synthesis

Journal of Nanoparticle Research, 2017, Vol 19, Issue 2, p1

1388-0764

Academic Journal

10.1007/s11051-017-3765-2