Rare Earths, N Doping Tio < Sub > 2 < / Sub > The Preparation Of Catalysts And Their Photocatalytic Performance Study

TiO₂photocatalysts have some good advantages, such as stability, strong oxidizing,low price, harmless effect to the environment and so on. It has become one of the mostpromising nano-photocatalyst technologies. But the Eg （3.2eV） is only response toultraviolet light. Therefore, how to improve the utilization rate of TiO₂on visible regionis the main content of the research. In this paper, La-N-codoped TiO₂andCe-N-codoped TiO₂were prepared. Meanwhile, the photocatalytic activity andmechanism were investigated through the photodegradation of phenol.La, N co-doped TiO₂（La-N-TiO₂） photocatalysts was prepared with a sol-gelmethod by using butyl titanate as titanium source, lanthanum nitrate and urea as adoping agent.Samples were characterized by the XRD, TEM, XPS, UV-vis and othermeasure method, results showed that codoping with La and N could significantlyenhance the thermostability and transformation temperature of anatase, extend the lightresponse range to490nm. Moreover, N existed as O-Ti-N and Ti-O-N while La as theLa-O-Ti. Use phenol as the model pollutants on its photocatalytic activity measurement.The results shows that photocatalysts calcined at500℃, lanthanum nitrate/TiO₂molarratio was1%,350W xenon lamp irradiation on20mg·L-1phenol for2h, the removal ratereached86.8%, and the COD removal rate can reach78.6%.Ce, N co-doped TiO₂（Ce-N-TiO₂） light catalyst was prepared via a non-aqueoussystem sol gel method by using titanium tetrachloride as a source of titanium, ceriumammonium nitrate and urea as a doping agent, and its was characterized on structureand properties. The results showed that Ce, N co-doped photocatalysts can not onlyinhibit TiO₂crystal phase transformation and improve the crystalline phase transitiontemperature, but also enhance the visible light absorption and absorption band edgeredshift up to502nm.Moreover, N existed as O-Ti-N while Ce as the Ce-O-Ti..At thesame time, the influences of different factors on the photocatalytic reaction processesaffected were investigated. The results showed that: ammonium ceric nitrate addition（relative to the TiO₂） was0.3mol%（molar ratio）, calcination temperature was at550 ℃,the sample on the phenol removal effect was best.When the catalyst concentrationwas2g/L, pH value was at5.68, simulated solar light irradiation time was120min, thephenol removal rate achieved93.8%, and the COD removal rate can reach83.4%.