摘要
CaTiO 3-Fex was characterized by X-ray diffractometry, scanning electron microscopy equipped with an energy dispersive spectrometry system, Fourier transform infrared spectra, and UV-visible spectra. Effects of Fe content on photocatalytic activity of CaTiO3-Fex were investigated through measuring photocatalytic degradation rate of methylene blue. The results show that chemical compositions of CaTiO3-Fex remained unchanged with increasing Fe content from 0 to 4.745%. However, the light absorption ability of CaTiO3-Fex exhibited a significant increase with increasing Fe content. Photocatalytic degradation of methylene blue over CaTiO3-Fex followed the first-order reaction kinetics. Based on changes of the concentration of methylene blue and its degradation kinetics, CaTiO3-Fe0.474% has shown to have optimal photocatalytic activity. The degradation rate of methylene blue over CaTiO3-Fe0.474% was almost 100% under UV-visible light irradiation for 3.0 h. The kobs of methylene blue over CaTiO 3-Fe0.474% was 1.33 h-1 and was 7 times that over CaTiO3-Fe0.
利用XRD、SEM-EDS、FT-IR光谱、UV-Vis光谱等多种方法对CaTiO3-Fex进行表征,通过测定亚甲基蓝的光催化降解率来考察铁含量对CaTiO3-Fex光催化活性的影响。结果表明,当铁含量从0增加到4.745%时,CaTiO3-Fex的化学组成几乎保持不变。但是,随着铁含量的增加,CaTiO3-Fex的光吸收能力显著增强。亚甲基蓝在CaTiO3-Fex上的光催化降解遵循一级反应动力学。基于亚甲基蓝浓度的变化及其反应动力学,CaTiO3-Fe0.474%显示出最佳的光催化活性。在紫外-可见光光照3.0 h时,亚甲基蓝在CaTiO3-Fe0.474%上的光催化降解达到100%。亚甲基蓝在CaTiO3-Fe0.474%上光催化降解的表观速率常数(kobs)为1.33 h-1,是其在CaTiO3-Fe0上光催化降解的kobs的7倍。
基金
Project(51090384)supported by the National Natural Science Foundation of China
Project(2012AA062304)supported by the Hi-tech Research and Development Program of China
Project(2012CBA01205)supported by the National Basic Research Program of China
Project(N110502002)supported by Fundamental Research Funds for the Central Universities,China
