TiO2纳米管阵列的制备及其光催化效率研究

以质量分数（下同）0.3%NH4F＋ethylene glycol＋1%H2O为电解液采用阳极氧化法制备了TiO2纳米管,研究了阳极氧化时间和退火温度对TiO2纳米管表面形貌、晶体结构和光催化效率的影响,比较了不同电解液制备的TiO2纳米管和溶胶凝胶法制备的TiO2薄膜的光催化效率.应用X射线衍射（XRD）和场发射扫描电镜（FESEM）对TiO2纳米管的形貌和结构进行了分析.结果表明：在阳极氧化恒电压50 V、阳极氧化48 h、450℃退火4 h条件下制备的TiO2纳米管具有最高的光催化效率,其光催化效率明显高于溶胶凝胶法制备的TiO2薄膜（4.4倍）,也高于0.5%HF电解液和弱酸水溶性电解液（0.5%HF＋1 mol/L NH4H2PO4）制备的TiO2纳米管的光催化效率.

Study on preparation and photocatalytic efficiency of TiO2 nanotube array

TiO2 nanotubes are prepared by anodic oxidation method with electrolyte comprised of water, NH4F, and ethylene glycol （mass fraction, same below, 0. 3 % NH4 F＋ ethylene glycol＋ 1% H2 O）. The influences of anodic time and annealing temperature on surface morphology, crystal structure and photocatalytic efficiency of TiO2 nanotubes are investigated, and the photocatalytic efficiencies of TiO2 nanotubes and films which are prepared by different electrolyzing solution and sol-gel method are compared. The morphology and crystalline phase of TiO2 nanotuhes are analyzed by FESEM and XRD. The results show that TiOz nanotuhes with anodizing voltage of 50 V for 48 h and annealed at 450 ℃ for 4 h possess the optimal photocatalytic efficiency which is not only much higher than that of the TiO2 film prepared by sol-gel method （4.4 times）, but also much higher than that of the TiO2 nanotubes prepared by electrolyte of 0.5M HF and weakly acidic water-solubility electrolyte （0. 5% HF＋ 1 mol/L NH4 H2 PO4 ）.