纳米TiO_2薄膜光催化降解苯酚的试验研究

Study on Photocatalytic Degradation of Phenol by Nano-TiO_2 Thin Films

采用交流磁控溅射法分别在载玻片、抛光单晶硅片(ITO玻璃)和铝片上制备出纳米TiO2薄膜,研究了薄膜厚度、退火温度及衬底对薄膜光催化降解苯酚性能的影响。结果表明:薄膜经500℃退火处理后TiO2由非晶态转变为锐钛矿结构,光催化降解性能得以提高;薄膜厚度在200nm以内时,随着厚度的增加则薄膜的光催化性能提高。比较了以玻璃、ITO玻璃和铝片为衬底制备的TiO2薄膜光催化降解苯酚的效果,结果表明,以铝片为衬底的降解效果最好,其在紫外光照射5 h后对苯酚的降解率达51%;ITO衬底次之;玻璃衬底的效果最差,不及铝片衬底的一半。

Nano-TiO2 thin films were prepared by AC magnetron sputtering on substrates such as glass, ITO glass and aluminum （Al） foil at room temperature. The photocatalytic characteristics of thin films with its annealing temperature, thickness and substrates for degrading phenol were studied. The results show that being annealed at 500 ℃, the modality of TiO2 thin films has become anatase from free formation, and its photocatalytic degradation of phenol is enhanced. Further, the degradation enhances with increasing of the thickness when the thickness of thin films is less than 200 nm. The degradation effects of the different TiO2 thin films on phenol are compared. The results show that the thin film of aluminum foil exhibits better photocatalytic activity than that of glass and ITO glass due to the forming of Schottky barrier between TiO2 and Al.