CuO/TiO_(2)复合材料制备与光催化性能研究

Study on Preparation of CuO/TiO_(2)Composite Material and Its Photocatalytic Performance

采用溶胶—凝胶法在550℃热处理条件下制备纯TiO_(2)及CuO/TiO_(2)复合光催化材料.通过X射线衍射、扫面电子显微镜和荧光光谱等方法对催化剂的晶体结构、微观形貌,以及光生电子和空穴复合率进行表征,并以亚甲基蓝作为目标污染物,研究其光催化性能.结果表明,采用550℃热处理工艺制备的纯TiO_(2)为锐钛矿结构,Cu元素加入后,TiO_(2)中出现了微量的金红石,促进了锐钛矿向金红石转变,并且产生了CuO相,形成了CuO/TiO_(2)复合材料.CuO的产生有利于抑制光生电子与空穴的复合,但CuO/TiO_(2)对亚甲基蓝的降解率低于纯TiO_(2),这可能是CuO/TiO_(2)复合材料的纳米颗粒团聚现象增强,比表面积降低所致.

Pure TiO_(2)and CuO/TiO_(2)composite photocatalytic materials were prepared by sol-gel method at 550℃.X-ray diffractometer,scanning electron microscope,fluorescence spectroscopy were used to analyze the crystal structure,surface morphology,and recombination rate of photogenerated electron and holes of the samples.Methylene blue,as a photocatalytic degradation target,was used to evaluate the photocatalytic performance of the prepared photocatalysts.The results show that the pure TiO_(2)exists as anatase crystalline phase at 550℃.Cu adding makes the emergence of a small amount of rutile,promoting the transformation of anatase to rutile.In addition,CuO phase is yielded,forming CuO/TiO_(2)composite material.The formation of CuO is useful to inhibit the recombination of photogenerated electrons and holes;however,the photocatalytic activity of CuO/TiO_(2)is lower than that of pure TiO_(2).This may be caused by the increased aggregation of nanoparticles of CuO/TiO_(2)composite material and the decrease in specific surface area.