新型上转光纳米TiO_2的制备及利用可见光降解SDBS的研究

PREPARATION OF NOVEL NANO TiO_2 CATALYST DOPED WITH UPCONVERSION LUMINESCENCE AGENT AND INVESTIGATION ON DEGRADATION OF SDBS USING VISIBLE LIGHT

合成了一种新型含有稀土金属Er的上转光剂,它在488nm可见光的激发下,产生了5个波长均小于387nm的上转换紫外发射峰。采用超声波分散的方法制备出了上转光剂掺杂的纳米TiO2可见光光催化剂。采用X-射线衍射(XRD)及透射电镜(TEM)对TiO2催化剂进行了表征。以十二烷基苯磺酸钠(SDBS)为研究对象,研究了在(三基色灯下发出的)可见光的照射下该催化剂的催化降解性能,并与未掺杂纳米TiO2粉末的催化性能进行了对比。实验结果表明,作为掺杂成分的上转光剂可有效地将可见光转化为紫外光并被纳米TiO2粉末吸收利用,在可见光照射50h后SDBS降解率达49.33%,高于未掺杂纳米TiO2的26.93%,为大规模利用太阳光处理工业废水开辟了道路,具有很好的应用前景。

In this research was synthesized a new upconversion luminescence agent, 40Cd F2· 60Ba F2· 1.2Er2O3, which can emit five upconversion fluorescent peaks with all wavelengths below 387nm under the excitation of 488nm visible light. The novel nanometer TiO2 photocatalyst dopped with the upconversion luminescence agent was prepared by ultrasonic dispersion and characterized by XRD and TEM. Its performance ofphotocatalytic degradation was studied with sodium dodecylbenzene sulfonate（SDBS） as studied object under the visible light irradiation by three-basic-color lamp, and was compared with the performance of the photocatalyst without doping with the upconversion luminescence. The results showed that the upconversion luminescence agent could convert visible light into ultraviolet light and was adsorbed and utilized by nanometer TiO2 powder; after irradiation by visible light for 50h, SDBS degradation rate reached to 49.33%, being greatly higher than 26.93% of the degradation rate without doping with TiO2 and creating a favourable condition for industrial wastewater treatment with large scale solar irradiation.