摘要
用溶胶–凝胶法制备铈(Ce)掺杂改性钛酸锶(SrTiO3)光催化剂,采用X射线衍射仪、红外光谱仪、扫描电子显微镜、能谱仪、粒度分析仪检测了改性SrTiO3的结构及表面性能,并通过催化降解亚甲基蓝考察了该SrTiO3的光催化性能。研究表明:Ce4+替代SrTiO3的Sr2+,使催化剂表面的Ti4+含量减少,粒径减小,比表面积增大,提高光生电子和空穴的利用率。Ce4+改性SrTiO3催化剂表面吸附氧和吸附H2O含量增加,导致光催化活性中心增多。Ce4+的4f能级使SrTiO3形成新的能带,并且循环捕获光电子还原为Ce3+,延长光生电子和空穴的寿命,提高SrTiO3的催化活性。掺杂3%(摩尔分数)Ce4+的SrTiO3对亚甲基蓝的降解率可达98.7%。
SrTiO3 doped Ce^4＋ photocatalyst was prepared by a sol-gel method. The properties of the doped SrTiO3 were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, BET specific surface area analysis, scanning electron microscopy and X-ray photo-electronic spectroscopy, respectively. The photocatalytic activities of the catalysts were evaluated by decolorization of methylene blue. The results show that Ti^4＋ content and crystalline size decrease, the specific surface area increases and the recombination of photo electrons and holes weakens when Sr^2＋ is replaced by Ce^4＋. Doping Ce^4＋ increased the amount of the adsorption oxygen and H2O on the improved SrTiO3 surface, leading to the increase of catalytic active center. Also, the 4f energy degree of Ce^4＋ reduced the band gap of SrTiO3 and enhanced the photoelectrons by the reduction of Ce^4＋ to Ce^3＋, consequently, the photoelectron lifetime and photocatalytic activity of the SrTiO3 doped Ce^4＋ were increased. The greatest activity was obtained and the degradation ratio of MB was 98.7% as SrTiO3 doped Ce^4＋of3% （in mole）.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2013年第4期547-552,共6页
Journal of The Chinese Ceramic Society
基金
重庆市重点攻关项目(CSTC 2011AC4070)资助
关键词
铈掺杂
钛酸锶
光催化
亚甲基蓝
cerium doping
strontium titanate
photocatalysis
methylene blue
