水热法制备WO3纳米棒阵列及其光催化性能

采用水热法，以Na₂WO₄·2H₂O为原料，NaCl为添加剂，直接在氧化铟锡透明导电基底上制备了有序WO₃纳米棒阵列.利用X射线衍射、扫描电子显微镜、透射电子显微镜和高分辨透射电子显微镜等手段对制备的纳米棒进行了表征，考察了pH值对产物形貌、尺寸和取向性的影响.结果表明:单根WO₃纳米棒具有六方单晶结构，随着前驱液pH值的增大，平行于基底生长的WO₃纳米棒捆逐渐转变为垂直于基底生长的纳米棒阵列.另外，对制备得到的两种不同取向的WO₃纳米棒结构进行了光催化降解甲基蓝溶液的研究，发现相比于WO₃纳米棒捆结构，纳米棒阵列的光催化性能更高. 

Hydrothermal preparation of WO3 nanorod arrays and their photocatalytic properties

WO₃ nanorod arrays were prepared on indium tin oxide (ITO) substrates by hydrothermal synthesis with Na₂WO₄·2H₂O as a raw material and NaCl as an additive. The nanorods were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. The effects of pH values on the morphology, size, and orientation of products were studied. The results show that the single crystalline WO₃ nanorod is hexagonal. When the pH value of the precursor solution increases, WO₃ nanorod bundles parallel to the substrate turn into nanorod arrays vertical to the substrate. In addition, two different orientation WO₃ nanorod structures were investigated by photocatalytic degradation of methyl blue solutions. It is found that the photocatalytic property of WO₃ nanorod arrays is better than that of WO₃ nanorod bundles.