Fe_(3)O_(4)/g-C_(3)N_(4)复合异质结的构建及紫外光降解罗丹明B

Preparation of Fe_(3)O_(4)/g-C_(3)N_(4)Composite Heterojunction and Its Photodegradation of Rhodamine B

本工作通过热聚合法生成了g-C_(3)N_(4),溶剂热法合成了Fe_(3)O_(4),并用高温煅烧法制备一系列不同质量比的g-C_(3)N_(4)/Fe_(3)O_(4)复合光催化剂。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)、荧光分光光度计对g-C_(3)N_(4)/Fe_(3)O_(4)复合材料的形貌、晶体结构、化学键结构以及荧光强度进行了表征;利用紫外-可见-近红外光谱仪对不同质量比g-C_(3)N_(4)/Fe_(3)O_(4)复合材料在250 W紫外灯照射下对罗丹明B降解情况进行测试,研究了不同质量比下复合材料的光催化活性,并对g-C_(3)N_(4)/Fe_(3)O_(4)最佳质量比(20/80)复合材料进行回收实验,测试其对罗丹明B的降解情况。结果表明:g-C_(3)N_(4)/Fe_(3)O_(4)最佳质量比(20/80)复合材料在2 h内对5 mg/L的罗丹明B的降解率可达到95.8%,回收五次后对罗丹明B的降解率依然能达到82.4%,表现出良好的光催化活性与催化稳定性。

In this work,firstly,g-C_(3)N_(4)was obtained by thermal polymerization,and Fe_(3)O_(4)was synthesized by solvothermal method.Subsequently,a series of g-C_(3)N_(4)/Fe_(3)O_(4)composite photocatalysts were prepared by high-temperature calcination via changing the mass ratio.The morpho-logy,crystal structure,chemical bond structure and fluorescence intensity of g-C_(3)N_(4)/Fe_(3)O_(4)composites were characterized by scanning electron microscopy(SEM),X-ray diffractometer(XRD),infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and fluorescence spectrophotometer.The degradation of rhodamine B via different mass ratios of g-C_(3)N_(4)/Fe_(3)O_(4)composites was tested by UV-Vis-IR spectrometer under the irradiation of 250 W ultraviolet lamp,and the photocatalytic activity of the composites photocatalysts was studied.Moreover,the recycling experiment of the optimal mass ratio(20/80)g-C_(3)N_(4)/Fe_(3)O_(4)composites was carried out to test the degradation of rhodamine B solution.The results show that the degradation rate of 5 mg/L rhodamine B reaches 95.8%by the mass ratio(20/80)g-C_(3)N_(4)/Fe_(3)O_(4)composite within 2 hours,and it’s degradation rate to rhodamine B still reaches 82.4%after five recycle times.It shows good photocatalytic activity and catalytic stability for the(20/80)g-C_(3)N_(4)/Fe_(3)O_(4)composite.