Fe2O3/TiO2异质结材料的制备及其可见光降解阿莫西林研究

New approach to preparing the heterojunction materials: synthesis and visible light-degradation of amoxicillin

为了拓宽TiO2的可见光响应范围,使其在可见光下能有效光催化降解阿莫西林,采用乳液法和浸渍法合成了Fe2O3包覆的Fe2O3/TiO2异质结材料,运用XRD、SEM、EDS、Raman、UV-Vis等技术对其进行了表征,并将其用于阿莫西林模拟废水的可见光催化降解,考察了催化剂用量、阿莫西林初始质量浓度、光照时间及重复使用次数对材料的光催化活性的影响。制得的样品为锐钛矿晶型,其颗粒粒径为280-350 nm,Fe2O3与TiO2之间形成了异质结结构,有效抑制了光生电子-空穴对的复合,拓宽了TiO2的可见光响应范围;此外,Fe2O3/TiO2异质结的光催化性能明显优于TiO2及Fe2O3;当Fe2O3/TiO2添加量为5 g/L、阿莫西林初始质量浓度为20 mg/L、光照60 min时,阿莫西林的去除率可达71.2%,且其重复利用性能良好。所制的Fe2O3/TiO2异质结材料能较好地光降解模拟废水中的阿莫西林,有望在抗生素废水的实际治理中得到应用。

The article is intended to introduce its work on how to expand the visible-light response range of TiO2and enhance the photocatalytic activities for degrading amoxicillin in the sewage under the visible light.It is just for this purpose that we have first of all synthesized the needed materials of Fe2O3coated Fe2O3/TiO2heterojunction with the emulsion and impregnation method.And,then,we have managed to identify the structure of the samples by applying the XRD,SEM,EDS,Raman and UV-vis technique.And,last of all,the visible-light photocatalytic activities and reusable performance of Fe2O3/TiO2have been traced and assessed so as to degrade amoxicillin and pursue its effects on the photocatalytic performance of the catalyst dosage,the initial amoxicillin mass concentration in addition to the visible-light irradiation time.The results we have gained indicate that the samples we have achieved are mainly of the anatase crystal type with their particle sizes being about 280-350 nm.As to the structure of the heterojunction we have gained,it has been resulted between Fe2O3and TiO2,which can effectively inhibit or present from the recombination of the photo-induced electronically hollow pairs and broaden the visible-light response range of TiO2.Besides,it has been made possible to improve the photocatalytic performance of Fe2O3/TiO2heterojunction obviously as compared to that of TiO2and Fe2O3.Furthermore,in the reaction conditions of Fe2O3/TiO2amount 5 g/L,it has been proved that the initial amoxicillin mass concentration can be made up to 20 mg/L and the visible light irradiation time shortened to 60 min,with the amoxicillin’s removal rate going up to 71.2%.And,simultaneously,the Fe2O3/TiO2heterojunction prepared in this way proves to display a nice reusable performance with no secondary pollution brought up to the environment.The practice of the 3 recycling adoption turns out to reduce the removing rate of amoxicillin by Fe2O3/TiO2heterojunction till less than 7%as well as below0.1 mg/L of the Fe concentration rate in the solution.Thus,it can be concluded that the method we have proposed can be successfully adopted o degrade amoxicillinin in the simulated sewage with the Fe2O3/TiO2heterojunction,which can surely be expected for its application to the actual antibiotic sewage treating practice.