摘 要:以氧化石墨为基体,以无水乙酸锌和氢氧化钾为原料,通过原位沉积工艺,将ZnO负载于氧化石墨表面;再以五水硝酸铋和碘化钾为原料,将BiOI负载于GO-ZnOI表面,制备氧化石墨基复合光催化剂(GO-ZnO-BiOI)。采用X-射线粉末衍射(XRD)、固体紫外可见漫反射(UV-vis)、扫描电子显微镜(SEM)等分析手段对产物进行了表征,并以可见光光催化降解甲基橙为探针,研究了氧化石墨改性前后的光催化性能。研究表明,产物的负载效果好、比表面大;随着铋含量的增加,光催化性能更好。其光催化活性顺序为GO-ZnO-BiOI > GO-BiOI>GO-ZnO;而且r= (nBi/nZn) 的比例对复合光催化剂的性能有明显影响,在可见光条件下,GO=70mg,r=3时显示出相对较好的光催化性能,3小时对10mg/L的甲基橙溶液的降解率达到99.43%。60014
毕业论文关键词:氧化石墨,氧化锌,碘氧化铋,甲基橙,可见光光催化
Abstract: In this article, we took the Graphite oxide as a substrate and used anhydrous zinc acetate and Potassium hydroxides as raw material to fabricate a series of ZnO composites by in-stiu coprecipitation method. Next BiOI was deposited onto GO-ZnO using potassium iodide and bismuth nitrate as raw materials. The obtained products were marked as GO-ZnO-BiOI and were characterized by X-Ray diffraction (XRD)、Ultra-violet-visible spectroscope(UV-vis) and scanning electron microscope(SEM). Results showed that GO was entirely exfoliated into a single flake during the synthetic process. ZnO-BiOI nanocomposite particles were successfully introduced onto GO’ surface without obvious aggregation and the specific surface area was successfully improved. Photodecomposition of methyl orange under visible light was chosen as the model system to evaluate the photocatalytic activity of obtained produces. Results showed that the photoactivity of the composite photocatalyst increase with the the dose of Bi (r= (nBi/nZn)), which decreased in the sequence GO-ZnO-BiOI > GO-BioI>GO-ZnO. Under visible light irradiation, the highest degradation rate of 10mg/L Methyl orange was 99.43% within 180 min obtained by using GO- ZnO-BiOI with GO=70mg,r =3.
Key word:Graphite oxide,Zinc oxide,BiOI,Methyl orange,Visible light photocatalysis
目录
1 前言 6
2 实验部分 7
2.1 试剂与仪器 7
2.1.1 实验原料与药品 7
2.1.2 实验仪器 7
2.2 光催化剂的制备与表征 7
2.2.1 氧化石墨负载氧化锌(GO-ZnO)的制备 7
2.2.2 氧化石墨负载氧化锌和碘氧化铋(GO-ZnO-BiOI)的制备 8
2.2.3 光催化材料的表征 8
2.3 光催化实验 8
3 结果与讨论 9
3.1 催化剂的表征 9
3.1.1 GO-ZnO,GO-BiOI和 GO-ZnO-BiOI 的XRD的谱图 9
3.1.2 SEM表征分析 10
3.1.3 UV-vis DRS分析 12
3.1.4 BET分析 14
3.2 复合材料催化剂的催化性能研究 15
3.2.1 无催化剂时甲基橙自身光催化降解研究 15
3.2.2 催化剂对甲基橙的催化效果 15
3.2.3 不同时间内GO-ZnO-BiOI的催化性能