Study On The Photocatalysis Of Tungsten And Nitrogen Co-Doped Titanium Dioxide

Nanometer photocatalysis technology application in the chemical industry is becoming more and more widely. The technology is in favor of environmental friendly development. Nanometer TiO2, with the advantages of good photochemical stability, high catalytic efficiency, strong oxidizing forces, harmless and cheap prices, plays an irreplaceable role in the field of photocatalytic TiO2. However, the catalytic activity of TiO2 should be supplemented by high-energy ultraviolet irradiation to be inspired and achieve the goal of catalysis. It brings great difficulties to use the solar energy to stimulate the catalytic performance of TiO2 for the photodegradation method implementation. Facilitating TiO2 inspired their catalytic activity under direct sunlight and possessing high catalytic efficiency, is the important directions of present exploration and research.The experiment in nitrogen and tungsten doping methods are based on activity of nanometer TiO2 photocatalyst, lower the temperature of preparation, sol of TiO2 prepared by low temperature. Titanium dioxide, nitrogen doping modification by tungsten and successfully improve the photocatalytic performance of the titanium dioxide. By using the method of low temperature sol, the disadvantages such as overcome preparation process to the high temperature calcination etc. can be controlled.The experiment content is based on 1:5 (volume) of deionized water and anhydrous ethanol, N/Ti (mol) 15%, W/Ti 0.05%(mol), temperature of 25℃. By simulating sunlight degradation of methyl orange, the degradation effect is obvious,60 min degradation rate is more than 90%, greatly improve the photocatalytic activity of TiO2. In terms of dynamics in tungsten doping titanium dioxide as catalyst and oxygen on the basis of principle of methyl orange photocatalytic degradation, this process is suitable for the law of the first order kinetics. Application of the first principle of the simulation study on the W and N-TiO2. On the basis of the optimal conditions and mesoporous silica composite, the optimum conditions are mass ratio SiO2/TiO2 30%, the sun for 60 min, degradation efficiency more than 85%, the production cost is reduced.Tungsten and nitrogen co-doped titania were characterized by means of XRD, SEM, XPS and FT-IR to analyze the crystal form and photocatalyst activity. The results show that the sample was anatase, and the powders were consisted of spherical particles, The photoresponse area extending into the visible range. The N dopant in the TiO2 lattice formed Ti-N to reduce the band energy to occur the visible response. The Fe dopants existed as W6+ to be the capture trap, enhanced the photocatalytic activity.