钛、铝和玻璃上TiO2光催化膜的失活研究

采用浸渍提拉法，在平行条件下制备了钛、铝和玻璃载体上的TiO₂膜TiO₂ / Ti、TiO₂ / Al和TiO₂ / G，利用X射线光电子能谱(XPS)、原子力显微镜(AFM)和光催化降解实验等手段对膜样品进行了表征和活性评价。实验结果表明，在铝和玻璃基材上制膜时发生了显著的基材元素溢出，使各膜样品的化学组成不同，同时TiO₂粒子和膜表面形貌也因前驱物烧结行为不同而差异较大。TiO₂

Deactivation of TiO2 Films on Titanium, Aluminums and Glass Substrates

TiO₂ films were loaded on Ti, Al and glass from Ti(OC₄H₉)₄ precursor by dip-coating method, represented by TiO₂ / Ti, TiO₂ / Al and TiO₂ / G, respectively. XPS, AFM and phtotocatalytic reaction experiments were carried out to characterize the catalytic films. The films prepared on different substrates varies greatly in chemical composition because of the extravasation of Al, Na, Ca, and Si from Al and glass substrates, which also influences the agglomerating behavior of the precursor films, resulting in the difference of particle sizes and morphologies of TiO₂ films. TiO₂ / Ti was proved to possess most stable photocatalytic activity, while TiO₂ /Al and TiO₂ / G deactivate obviously with the increase of photocatalytic experiment runs. It is concluded that accumulation of surface carbon species such as reactive intermediate was not the dominant cause of deactivation in this research. The remarkable leaching and chemical alternation of extravasated elements brought out intergranular corrosion of TiO₂ films on Al and glass, leading to the flake-off of outmost TiO₂ particles. The new surface contained three chemical states of Ti: Ti⁴⁺, Ti³⁺ and Ti²⁺, which was different from the new prepared TiO₂ films with high activity, possessing only Ti⁴⁺.