摘要:本文以凹凸棒土为基体,以碘化钾、五水硝酸铋、钛酸四丁酯为原料,采用原位沉积法制备了一系列BiOI-TiO2(r=nTiO2/(nTiO2+nBiOI)=0.2、0.25、0.33、0.50、0.67、0.75、0.80)复合氧化物包覆凹凸棒土的可见光复合催化剂(产物标记为Att-BiOI-TiO2-r)。采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、比表面(BET)、紫外可见光谱(UV-Vis)等分析手段对产物进行了表征,对所合成的光催化剂的结构、形貌及其光催化性能进行了深入的研究。以甲基橙为降解模型系统,对不同比例的Att-BiOI-TiO2的可见光催化活性进行了研究。结果表明:经过氧化物包覆改性后,凹凸棒土的光催化性能得到明显提高,而且BiOI-TiO2复合氧化物的包覆配比不同,Att-BiOI-TiO2光催化性能不同。当r=0.2和 r=0.75时,复合材料的光催化效果最佳,可见光降解2h后,甲基橙的降解率分别达97.74 %和96.21 %,论文也对Att-BiOI-TiO2的光催化作用机理进行了探讨。54263
毕业论文关键词:可见光,凹凸棒土,BiOI-TiO2,原位-沉积,光催化
Abstract: In this article, attapulgite(Att) was taken as a substrate to fabricated composite visible light photocatalyst by a series of coating different proportion of BiOI-TiO2(r=nTiO2/(nTiO2+nBiOI)=0.2、0.25、0.33、0.50、0.67、0.75、0.80)onto its surface using in-situ depositing technique. The obtained products were marked as Att-BiOI-TiO2-r and were characterized by XRD, SEM, BET and UV-Vis techniques. Results showed that the surface morphology of the original attapulgite was effectively reformed and the specific surface property was successfully modified. Visible light degradation of methyl orange was used as the model system to investigate the visible light photocatalytic activity of the composite photocatalyst. the effect of ratio was also studied. The decomposition rate of 10 mg/L methyl orange was achieved to 97.74 % and 96.21% within 2 h by using Att-BiOI-TiO2-0.2 and Att-BiOI-TiO2-0.75 as the photocatalyst, respectively. Proposed mechanism of photocatalytic activity enhancement was put forward.
Keyword: Visible light, Attapulgite, BiOI-TiO2, In-situ deposite, Photocatalysis
目 录
1 前言 3
2 实验内容 4
2.1 试剂和仪器 3
2.2 复合光催化剂的制备 4
2.2.1 Att的初提成 4
2.2.3 Att-BiOI光催化剂制备 4
2.2.4 Att-BiOI-TiO2光催化剂制备 4
2.3 材料表征 4
2.4 材料的光催化性能 5
2.5 COD去除率的测试 5
3 结果与讨论 5
3.1 催化剂的表征 5
3.1.1 XRD分析 5
3.1.2 SEM结果分析 7
3.1.3 BET结果分析 8
3.1.4 UV-vis 9
3.2 催化剂的催化性能研究 10
3.2.1 Att-BiOI-TiO2的光催化效果研究 10
3.2.2 不同催化剂对甲基橙催化降解效率的曲线图 11
3.2.3 不同比例复合光催化剂对甲基橙催化降解效率的曲线图 12
3.3 Att-BiOI-TiO2光催化机理的探讨 13