摘要
采用溶胶 -凝胶 -浸渍法制备了掺杂La3+ 并沉积Pt的TiO2 粉体光催化剂 ,考察了它对直接耐晒蓝的降解效果。结果表明 ,以TiO2 干凝胶为母体 ,依次浸渍La3+ 、Pt4 + 所制备的粉体光催化剂La3+ /Pt/TiO2 降解效果比纯TiO2 高 80 % ,比相应的La3+ /TiO2 高 3 6% ,比Pt/TiO2 高 10 .9%。X射线衍射分析表明 ,该法制备的TiO2 粉体中锐钛矿相占 95 %以上 ,没有镧的氧化物形式 ,Pt以纳米级原子簇的形式沉积在La3+ /TiO2 表面 ,平均晶粒粒径为 7nm ,小于TiO2 的平均粒径 10nm ;红外吸收光谱分析表明 ,无论是纯TiO2 还是经过掺杂金属离子、掺杂与沉积贵金属共用后的TiO2 ,红外吸收光谱图相似 ,说明掺杂和沉积贵金属并没有极大地改变TiO2 的化学结构 ,光催化性能的提高取决于杂质能级的电子捕获陷阱作用和光生载流子的重新分布。沉积贵金属有利于分离电子 -空穴对 ,但沉积量不宜过大。
TiO2 photocatalyst which was doped with La^3＋ and deposited Pt was prepared by using sol - gel - immersion method. Its degradation effect on direet fast blue was investigated. The results demonstrated that degradation effect ofLa^3＋/Pt/TiO2 with TiO2 dry gel as motherbedy, after La^3＋, Pt^4＋ was in turn immersed, was 80% higher than that of TiO2, 36 % higher than that of La^3＋/SiO and 10.9% higher than that of Pt/TiO2. XRD analysis indicated that anatase phase in TiO2 was more than 95%, no oxidation phase of La^3＋ , Pt was deposited on the surface of Las ＋/TiO2, which was namometer- order atom. The mean crystal diameter was 7nm. FTIR analysis indicated that metal - ion doping and noble metal depositon eould not greatly ehange the ehemieal strueture of TiO2. Photoeatalyfie aetivity was promoted because of eleetron - traetor effect of La^3＋ and redistribution of photogenerated carriers. The deposition of noble metal was favorate to separate eleetron - hole pairs, but the effeet of degradation was worse for higher deposition.
出处
《南昌航空工业学院学报》
CAS
2004年第1期74-78,共5页
Journal of Nanchang Institute of Aeronautical Technology（Natural Science Edition）
基金
陕西省教育厅专项科研基金资助项目 (0 0JK2 0 8)
