Study On The Preparation And Photocatatytic Propetries Of N-doped Titanium Dioxide

Nowadays, the control of environmental pollution and the use of solar energy arethe most important issues in the world. People pay attentions to the problem how totake advantage of sunlight in the degradation of pollutants. Therefore, it is necessaryto explore a kind of catalytic material. The catalyst is low cost and showhigh-performance under sunlight. The discovery of this environment-friendly materialwill bring huge social and environmental benefits. As a very promising photocatalyst,TiO₂has a lot of properties. It has good stability and low price. The most importantfact is that it is nontoxic and harmless, which can solve the secondary pollutionproblem. However, TiO₂has the shortage that its catalytic activity can only showunder ultraviolet light rather than the visible light. While the majority of the visiblelight in sunlight is difficult to be effectively utilized, the application of TiO₂is limited.In order to improve the photocatalytic activity of TiO₂, people have tried manydifferent modification methods. In this paper, a simple N-doping method has beenexplored. A special characteristic of TiN was used. When TiN is not completelyoxidized, it can become N-doped TiO₂catalyst. In the preparation of the catalystparticles experiment, nanomaterial TiN was sintered under aerobic conditions. Theobtained catalysts was characterized by several characterization methods. Thenphenol was taken as the target pollutant to verify the catalytic activity of the catalystunder visible light.In this paper, nanomaterial TiN was uesd as the raw material. The nitrogen dopedtitanium oxide catalysts was obtained by the oxidation of TiN under atmosphericpressure. The results show that:（1） With the calcining temperature increases, the size of particle increases. Thecrystalline phase tends to be mature. The absorption position of catalyst shows redshift.（2） As phenol is the target pollutant, the nitrogen-doped titanium dioxide catalyst shows good visible light photocatalytic activity. The maximum removalefficiency reaches97.35%.（3） The calcining temperature has great impact on thecatalytic activity. When the temperature is650℃, the catalytic activity is best.（4）With the increase of catalyst dosage, the catalytic efficiency gradually improves.However, when the catalyst dosage increased to0.5g/L, the continuative increase willhinder the catalytic reaction.（5）The initial concentration of phenol and thedegradation rate shows a decreasing relationship. The smaller the initial concentration,the greater the degradation rate of the phenol.（6）The calcing method makes titaniumdioxide part redshift, but it is still difficult to make use of the visible light more than440nm.（7） The catalyst can be reused for many times. When it is cycled for fourtimes, the phenol degradation efficiency just decreases1.6%.