纳米TiO2光催化剂的最新发展——多孔TiO2

介绍了多孔TiO2的溶胶-凝胶制备法和模板制备法，评述了其光催化活性，并从孔径大小、比表面积、煅烧温度和煅烧时间4个方面探讨了多孔TiO2光催化活性的影响因素。孔径在介孔范围内的多孔TiO2,可以对待降解物进行吸附，反应物和生成物的扩散速度加快，光催化活性和催化速率得到提高；TiO2中适量孔的引入，增加了催化剂的比表面积，有利于催化剂与反应物的充分接触，提高光催化活性；煅烧温度过高，容易导致多孔TiO2光催化剂孔结构的坍塌，影响其光催化活性；煅烧时间太短，催化剂未形成或未完全形成锐钛矿型，催化作用减弱；煅烧时间太长，晶粒则会太大，光催化活性降低。因此以合适的制备工艺条件将TiO2制成多孔结构是提高其光催化活性的有效途径之一，具有重要的研究价值和很好的应用前景。

The Latest Development of Nanometer TiO2 Photocatalysts——Porous TiO2

This paper introduces the preparative methods of porous TiO2 photo-catalysts from sol-gel and template,and then recommends their photo-catalytic activity.The influencing factors have been discussed from porous diameter,specific area,calcinations temperature and time.When the diameters of these porous in the range of mesoporous,organic compounds waiting for degradation would be adsorbed,and the diffused velocity of reactants and resultant would be increased,photocatalytic activity and velocity would be improved.Moreover,specific areas of photo-catalysts are enhanced after proper quantities porous had been made in TiO2,which is propitious to keeping in touch with reactants and promoting the photo-catalytic activity.Calcinations temperature too high,porous structures easy to collapse,and the photo-catalytic activity is influenced.Calcinations time too short,photo-catalysts couldn't form to complete anatase and degrade the photo-catalytic effective.While,calcinations time too long,grain size could be increased and the photo-catalytic activity could be reduced.So Porous TiO2 prepared with proper processing conditions is an effective approach to improve photocatalytic activity of TiO2,have a good research value and applied prospect.