【摘要】 为拓展二氧化钛对可见光的响应,以尿素为氮源,在温和条件下采用溶胶-凝胶法制备了氮掺杂二氧化钛粉末.用X射线衍射、透射电镜扫描、紫外-可见光漫反射吸收光谱和X射线光电子能谱等方法对制备的样品进行了表征,对可见光照射下的光催化活性进行了测试,并考察了煅烧温度及氮含量对光催化活性的影响.结果表明:氮掺杂致使二氧化钛在可见光区的光吸收增强,在降解甲基橙的实验中表现出良好的可见光催化活性;随煅烧温度的增加,氮含量减少,晶粒增大,可见光催化活性减弱;400℃下制备的样品中存在一个最佳的N/Ti配比,所对应的可见光催化活性最高.更多还原

【Abstract】 In order to expand the optical response of titania into the visible-light region,nitrogen-doped titania powders with urea as the nitrogen source were prepared by sol-gel method in mild conditions.The prepared samples were then characterized using XRD,TEM,UV-Vis diffuse reflectance spectrophotometer and X-ray photoelectron spectroscopy.Moreover,the photocatalytic activities of the samples in the visible-light region were tested,and the influences of calcination temperature and nitrogen content on the photocatalytic activity were investigated.The results indicate that(1) the doping of nitrogen leads to an increase in optical absorption intensity in the visible-light region,which results in a high visible-light photocatalytic activity with nitrogen-doped titania in the decolouration of methyl orange;(2) with the increase in calcination temperature,the nitrogen content decreases,the crystallite size enlarges,and the visible-light photocatalytic activity weakens;and(3) there exists an optimum N/Ti proportion for the catalysts calcined at 400℃,which results in the highest visible-light photoctalytic activity.更多还原