Controllable One-Pot Synthesis and Enhanced Visible Light Photocatalytic Activity of Tunable C-Cl-Codoped TiO2 Nanocrystals with High Surface Area

We demonstrate the controlled synthesis of C-Cl-codoped anatase TiO2, nanocrystals by hydrolysis of titanium tetraisopropoxide (TTIP) in chloroform containing trace amounts of water at a low temperature of 150 degrees C without subsequent thermal procedure. The C and Cl dopants resulted from the solvothermal decomposition of chloroform induced by water, and the adjusting of molar ratios of water to TTIP was able to tune the crystal sizes and the concentration of the dopants. The as-prepared powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), nitrogen adsorption, X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (DRS). All the C-Cl-codoped TiO2 possessed mesoporous Structure and high Surface areas between 158.1 and 469.6 m(2)/g. The photocatalytic activities of the resulting C-Cl-codoped TiO2 nanocrystals were evaluated by the photodegradation of RhB Under visible light irradiation. The sample synthesized with it molar ratio of water to TTIP equal to 2 exhibited the highest photoactivity among all the synthesized C-Cl-codoped TiO2. Its activity was even much higher than that of the C-TiO2 and Cl-TiO2 reported in our previous work. The enhanced visible light photocatalyitc activity of that C-Cl-codoped TiO2 nanocrystal Could be primarily attributed to the large surface area and the synergetic effect of the codoping.