Preparation of N-doped mesoporous TiO2 nanorods Typically, 5 mL of tetrabutyl titanate (TBOT), 30 mL of ethanol, and certain ammonium nitrate were mixed together in the reaction flask of the rotary evaporator, and ten agate granules with a diameter of about 1 cm were added into the system for better stirring. The rotary evaporator was turned on and the system was maintained at 25°C. In the mean time, an air blower connected with a round bottom flask containing some deionized

water was turned on to transport air at a rate of 40 L min-1. A small amount of water vapor was carried into the reaction flask with air to react with the TBOT. CBL0137 supplier The TBOT solution was hydrolyzed slowly to form a cream color emulsion. Reaction stopped after 3 h and then the emulsion was distillated at 50°C for 15 min under vacuum. Finally, the samples were annealed at different temperatures for 2 h to obtain the N-doped mesoporous TiO2 nanorods, designated as NMTNR-x-y, where x represents the theoretical molar ratio of N (%) and y represents the calcination temperature (°C). Characterization of the samples The crystalline phase identification and structural analysis were carried out by X-ray diffraction (XRD) instrument with

Cu Kα radiation. A Japan ULVAC-PHI PHI 5000 VersaProbe selleck inhibitor X-ray photoelectron spectrometer (XPS; Kanagawa, Japan) was applied to analyze the elemental composition and state of the samples. The microstructures were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). N2 adsorption-desorption isotherms were measured at 77 K on a Micromeritics Tristar 3020 system (Norcross, GA, USA). The UV-visible (UV–vis) absorbance spectra of the samples were characterized

using a Japan Shimadzu UV240 UV–vis spectrophotometer (Kyoto, Japan). Photocatalytic activity The photocatalytic activity of the samples was estimated by MB degradation performed in a 500-mL cylindrical glass photocatalytic reactor, and a 500-W xenon only lamp was selected as the visible light source. Between the xenon lamp and reactor, a cut filter was inserted to eliminate ultraviolet light. In a typical experiment, 0.08 g of photocatalyst was dispersed into 250 mL of MB solution (10 mg L-1). The actual effect of photocatalytic activity by chemical reaction was studied by maintaining the solutions in the dark for 1 h before irradiation. The MB solution (5 mL) was taken out every 5 min and analyzed using UV–vis spectrophotometer. The degradation of MB can be calculated via the formula η = (1 – A i /A 0) × 100%, where A 0 is the absorbance of the original MB solution before irradiation and A i is the absorbance of MB solution measured every 5 min. The photodegradation of MB follows pseudo-first-order kinetics. Its kinetics can be expressed as ln(C 0/C) = kt, where k (per minute) is the degradation rate constant.