三氧化钨纳米线的制备及其光催化性能

Preparation and Photocatalytic Properties of WO 3 Nanowires

以Na2WO4·2H2O和HCl为原料,采用水热法合成了WO3,并用X射线粉末衍射(XRD)、扫描电镜(SEM)、紫外漫反射(UV-Vis)、电子能量分散谱(EDS)和激光拉曼光谱(Raman)测试手段对样品进行表征。测试结果表明,Na2SO4作为添加剂时水热合成的产物皆为六方相三氧化钨纳米线,其粗细和长短略有差异,不同浓度的Na2SO4对产品晶型和形貌无影响,但影响其晶粒尺寸,其中0.125M Na2SO4所得六方相WO3纳米线的尺寸最小,平均直径约为5nm,长度约为1um,并具有最佳的光催化活性,可见光(≥420 nm)照射150min罗丹明B溶液后的降解率达96.01%。

WO3 were prepared by hydrothermal method using Na2WO4·2H20 and HC1 as raw materials. The samples were character- ized by X-ray diffraction （ XRD ）, scanning electron microscope （ SEM ）, and UV-Vis diffusion reflectance spectra （ UV-vis ）, electron energy spectrum dispersion （EDS） and laser Raman spectroscopy （Raman） measurements. The results show that the products via hy- drothermal process are hexagonal WO3 nanowires with Na,2SO4 as additive, and the thickness and length of nanowires have a slight difference, suggesting that different concentrations of Na2SO4 have certain influence on the grain size, but no effect on the crystal form and morphology. Photocatalytic degradation of rhodamine B solution （ 1×10^-4mol/L） show that hexagonal WO3 nanowires prepared in the presence of 0. 125 M NazSO4 has smallest size, the average diameter and length of the sample are respectively 5 nm and 1 urn, exhibiting the best photocatalytic activity, and its degradation rate of rhodamine B solution is 96. 01% under visible-light irradiation （≥ 420 nm） after 150 min.