具有超快吸附能力的(C,N)-TiO_2光催化材料  

Preparation and Photocatalytic Properties of Nitrogen and Carbon Co-doped Titanium Dioxide by Combining Sol-gel Method and Microwave-assisted Method

作　　者：何琴玉[1,2] 吴泽宏[1] 黄伟源[1] 陈晓媚[1] 魏玉蕊 刘俊明[2] 杜纯[1] 周江山[1] 李方舟[1] 

机构地区：[1]华南师范大学物理与电信工程学院,广东省量子工程与量子材料重点实验室,广州510006 [2]华南师范大学华南先进电子研究院,先进材料实验室,广州510006

出　　处：《华南师范大学学报（自然科学版）》2016年第5期25-30,共6页Journal of South China Normal University(Natural Science Edition)

基　　金：国家自然科学基金项目(51372092);华南师范大学2014-2015年自然科学类“高校创新强校工程”特色创新类项目

摘　　要：采用"溶胶-凝胶与微波二步法"合成了碳、氮掺杂的锐钛矿(C,N)-TiO_2光催化材料.首先采用溶胶-凝胶方法制备了TiO_2前驱物凝胶粉末,然后将其与盐酸胍混合微波制备(C,N)-TiO_2纳米材料.对该材料进行X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外-可见漫反射光谱(UV-Vis DRS)等表征,并测试在甲基橙溶液(100mg/L)中的黑暗吸附以及饱和黑暗吸附后的甲基橙光催化降解等性能.结果表明,获得的材料为纯锐钛矿相的二氧化钛.颗粒分散好,平均粒径约20 nm.具有大的比表面积.随着C、N含量的增加,可见光区域的吸收增加,而紫外光区域的吸收基本不随C、N的含量变化;所制备的(C,N)-TiO_2对甲基橙溶液具有超快的黑暗吸附能力(t<1min);在微波处理中,随着盐酸胍的添加量增加,光催化的量子效率先增加后减小.最好的样品能在20 min内对甲基橙的降解效率达到93%.在可见光区域的吸收与黑暗吸附2个因素中,黑暗吸附的作用更大.文章认为微波处理光催化材料的方法简单、快速、节能,是提高光催化速率的有效途径,值得推广.A kind of nitrogen and carbon co-doped titanium dioxide（（ N,C）-TiO_2） was prepared by a simple,fast and energy-saving method,by which composite consisting of TiO_2precusor（ fabricated by sol-gel method） and guanidine hydrochloride was irradiated by microwave. X-Ray diffraction（ XRD）,scanning electron microscopy（SEM）,UV-visible diffuse reflection spectra（UV-Vis DRS）,dark adsorption of methylene orange and photo-catalysis were employed to characterize the prepared samples. It is shown that the prepared samples are pure anatase TiO_2 with large specific area and good disperse,homogeneous nanosized particle size（20 nm）. The Vis absorption of prepared powders increases with increased content of guanidine hydrochloride in above-said composite. In the meantime,a very fast and high dark adsorption is found in as-fabricated powders. The time when the dark adsorption reaches to saturation is less than 1 min. And the photocatalytic degradation firstly increases,then decreases with increased content of guanidine hydrochloride in above-said composite. The best saturated photocatalytic degradation is 93% within 20 min. It is also found that between the two factors-Vis absorption and dark adsorption,the dark adsorption plays more important role in photocatalytic activity. It can be concluded that the microwave-assisted method can introduce pores or lead to smaller particle size in as-prepared powdered photocatalysts.

关 键 词：碳、氮掺杂二氧化钛 黑暗吸附 光催化 甲基橙 

分 类 号：O64[理学—物理化学]