WO 3·H 2O纳米线阵列的制备及其光催化活性

制备了具有有序孔洞多孔阳极氧化铝 (AAO) , 并以之为模板通过溶胶2凝胶法制备高度取向的WO 3·H 2O纳米线阵列 , 用 X射线衍射、XPS、 扫描电镜 (SEM) 和比表面积仪进行表征。结果表明 : WO 3·H 2O纳米线线径与 AAO模板的孔径一致 , 且分布均匀 , 线径为 26 nm , 线长为 1. 1μm; 与相同条件下用玻纤布作载体制备的 WO 3·H 2O膜相比 , 其平均晶粒小 , 低密度 , 高比表面积。将催化剂 WO 3·H 2O/ AAO与 WO 3·H 2O/玻纤布两者分别对气相甲醛进行光催化降解反应以评价它们的光催化活性 , 得出 WO 3·H 2O纳米线阵列光催化降解气相甲醛反应速率常数大约是 WO 3·H 2O/玻纤布的 3. 4 倍 , 说明以 AAO 为模板制备的 WO 3·H 2O纳米线阵列具有更高的光催化活性。

Synthesis of WO 3·H 2O nanowire arrays f ilm and its photocatalytic activity

The highly ordered porous anodic alumina ( AAO) membrane was synthesized , and using it as template , the WO 3 ·H 2O nanowire arrays with good orientation were prepared by the sol 2 gel method. The product s are characterized by X2ray Diff raction and XPS , Scanning Elect ron Microscopy and Specific Surface Area Inst rument . And the result s show that WO 3 ·H 2O nanowires are uniformly dist ributed , and the diameters are consistent with the pores of the AAO template , about 26 nm in diameter and 1. 1μm in length. Compared with the WO 3·H 2O film on fiberglass cloth as carrier , the WO 3 ·H 2O nanowires have a smaller crystallite size , less density and larger specific surface area. Photocatalytic activities of the WO 3 ·H 2O/ AAO and WO 3 ·H 2O/fiberglass cloth were measured by degradation of gaseous formaldehyde respectively , and the rate constant of photocatalytic reaction is about 3. 4 times that of the WO 3·H 2O/ fiberglass cloth film. It is indicated that the WO 3 ·H 2O nanowires arrays synthesized as AAO template have higher photocatalytic activity.