Adsorption and photocatalysis of spherical TiO2 particles prepared by hydrothermal reaction

TiO2 spherical particles were prepared using a hydrothermal reaction at different temperatures (110, 150, and 190 °C) for 5 h. The TiO2 samples were characterized by Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). The specific surface areas and particle sizes were in the range 148–240 m2/g and 323–450 nm, respectively, and the particles were composed of tiny nanoparticles with a size of 5–7 nm in diameter. It was found that the photocatalytic degradation of methylene blue is highly sensitive to the influence of the particle size on the adsorption and photocatalysis.