Basic Research, <sub> Of Tio 2 </ Sub> Photocatalyst Modification And Degradation Of Dye

Because of its light stability and high efficiency, titanium dioxide as aphotocatalyzer has become a hotspot of domestic and international studyat present. In recent years, scientists pay more and more attention tophotocatalysis oxide method. As an advanced oxidation processes (AOPs),photocatalysis oxide method has many merits, for example:photocatalysis processes are simple, TiO₂ materials can be easily got, andhas good stability and low price etc. But, seen from the utilizationefficiency of solar energy, it has a lot of disadvantages. First, the waveband of TiO₂ for light absorption is narrow, mostly located in the area ofultraviolet radiation. While to the visible-light or room-light, itsphotocatalysis efficiency is very low. Second, recombining rate of theelectron flow of TiO₂ semiconductor is high, and quantum efficiency islow; then, many studies founce on the modification of titanium dioxide.The investigations on the preparation method, application of TiO₂ as aphotocatalyst, the mechanism, kinetics and technology of photocatalytictreatment of organic dye with TiO₂ and the nitrogen-doping studies ofTiO₂ for improving photocatalysis properties are systemicallysummarized, then, experimental studies were carried out on thelaboratory scale in this article:First, the study on photocatalytic degradation of organic substance:Reactive brilliant red X-3B with azo-group was used as treatmentproject, two aspects were studied .First, the mechanism of photocatalyticdegradation of organic substance under different lamp-house. Second, theeffect factors and the kinetic of photocatalytic degradation X-3B undervisible light in TiO₂ suspension system. The study used analyticalmethods such as UV-Vis absorption spectrum, Ion chromatography, TOCetc.Second, the preparation techniques and characterizetion of thenitrogen-doped titanium oxides:In this study, a style of high visible-light active nitrogen-doped TiO₂powder was prepared by this process: tetrabutyl titanate was hydrolyzed by saturated solution of urea to obtain white hydrated titanium dioxidepowder, then, calcined the white powder in ambient atmosphere at 400 to700℃for 2h,at last, obtained nitrogen-doped TiO₂. In this process,nitrogen-doping reaction could be accomplished at low temperature:nitrogen source was import into the hydrated titanium dioxide in theprocess of hydrolyzing, nitrogen-doping reaction accomplished whilehydrated titanium dioxide turning into the crystal type TiO₂ bycalcined .The size, absorbency and other character of obtained sampleswere characterized by XRD, BET and UV-Vis; the nitrogen-dopingprocess and the presence of nitrogen element in the samples wereanalyzed by TG-DTA, FT-IR and XPS.This study has great significance to apply the technology ofphoto-catalysis to the industry of treat organic waste water.