材料期刊网

WO 3是一种带隙约为2．6 eV 过渡金属半导体,可见光便能激发其光催化活性,这极大地提高了太阳光的利用率,但纯 WO 3纳米材料催化活性较低,针对这一难题,国内外研究者大多采取对其表面改性来提高它的光催化性能,对WO 3本身进行原位研究的报道极少。实验致力于改进 WO 3纳米材料的形貌结构来拓展其光催化性能。分别采取 CaCl2和 Na2 SO4为诱导盐,Na2 WO4为 W 源,在一定的 pH 值条件下水热制备WO 3纳米网格和纳米线；并研究了这两种不同形貌结构的 WO 3纳米材料的光催化活性。研究表明,WO 3网格立体网格结构具有更好的催化性能。实验发现 WO 3网格独特的层状结构能减少太阳光的逃逸,增强对光的吸收；网格结构具有更大的比表面积,能增加光催化过程中催化剂与有机物的反应活性点；这两点可能是立体网格结构 WO 3促进光催化反应的重要原因。

Due to WO3 with the band bap of about 2.6 eV,visible light can stimulate its photocatalytic activity, which greatly enhance the utilization rate of sunlight.However,the photocatalytic activity of pure WO3 nanop-owder was relatively low.In order to solve this problem,most of the domestic and foreign researchers have in-vestigated the surface modification of WO3 to improve its photocatalytic activity,whereas in situ studies of WO3 itself have been rarely reported.This project will be committed to modulate morphology of WO3 nanostructures to improve its photocatalytic performance.WO3 nanonetworks and nanowires have been prepared in the presence of CaCl2 and Na2 SO4 respectively.XRD,FESEM and TEM were employed to characterize the sample.To ex-plore the photocatalysis originated from the structure,the photodegradation of methylene blue was carried out under simulated sunlight irradiation.The result displayed that the nanonetwork showed a higher photocatalytic activity owing to its novel hierarchical structure.Our investigation demonstrates that nanonetwork hierarchical structure can promote sunlight absorption and increase the reaction active site due to higher specific surface area.