可见光响应的介孔TiO_(2)光降解罗丹明B机制及其降解途径  

Photodegradation mechanism and pathway of visible light-response mesoporous TiO_(2) for Rhodamine B

作　　者：王国琴 付小航 朱羽科 吴礼光[1] 王挺[1,2] 蒋孝佳 陈华丽 WANG Guoqin;FU Xiaohang;ZHU Yuke;WU Liguang;WANG Ting;JIANG Xiaojia;CHEN Huali(School of Environmental Science and Engineering,Zhejiang Gongshang University,Hangzhou,Zhejiang 310012,China;Instrumental Analysis Center,Zhejiang Gongshang University,Hangzhou,Zhejiang 310012,China)

机构地区：[1]浙江工商大学环境科学与工程学院,浙江杭州310012 [2]浙江工商大学分析测试中心,浙江杭州310012

出　　处：《纺织学报》2023年第5期155-163,共9页Journal of Textile Research

基　　金：国家自然科学基金项目(21776250);浙江省自然科学基金项目(LY19B060004,LY20B060001)。

摘　　要：为获得可见光响应的高效介孔TiO_(2)光催化剂,利用软模板法制备了螺旋堆积的手性介孔TiO_(2)。对比分析了手性介孔TiO_(2)和非手性介孔TiO_(2)的差异。通过自由基捕获实验和电子自旋共振(ESR)光谱,结合福井指数(f-)的计算探索了手性介孔TiO_(2)降解罗丹明B(RhB)的机制和路径。结果表明,手性介孔TiO_(2)的螺旋堆积结构引入了更多缺陷,从而其Ti^(3+)和氧空穴的含量都高于非手性介孔TiO_(2),因此具有更强的可见光响应和降解活性,其对RhB的去除率超过非手性介孔TiO_(2)的4倍;手性介孔TiO_(2)降解有机污染物分子的主要活性物种是光生空穴h+;越容易给出电子的原子位点(即f-值越高)越容易受到h+的攻击发生降解;降解过程中中间产物分析进一步得到了可见光激发手性介孔TiO_(2)降解RhB的主要路径。Objective In order to promote the practical application of deep treatment of organic pollutants in slightly polluted water bodies using heterogeneous photocatalysis,mesoporous TiO_(2) photocatalyst as a novel photocatalyst with a pore size of 2-50 nm has a particle size of larger than 200 nm,so it was very easy to recycle,thus avoiding the potential nano-toxicity of the nano photocatalyst.Method In order to obtain a visible-light-responsive mesoporous TiO_(2) photocatalyst,chiral mesoporous TiO_(2) with spirally-stacked structure was prepared by a soft template method constructed with chiral surfactants.By means of various characterization methods such as X-ray spectroscopy,scanning electron microscopy,X-ray photoelectron spectroscopy,surface area and pore size analysis,and circular dichroism(CD),the differences in structure and visible light response of chiral mesoporous TiO_(2) and achiral mesoporous TiO_(2) were compared and analyzed.The photodegradation experiment for Rhodamine B(RhB)under visible light excitation was adopted to evaluate their catalytic performance,thus exploring the mechanism and pathway for degrading RhB by chiral mesoporous TiO_(2).Results The average pore diameters of the two mesoporous TiO_(2) were 6.4 nm and 8.6 nm.The specific surface area,pore volume and pore size of chiral mesoporous TiO_(2) prepared by chiral surfactants were slightly smaller than those of achiral mesoporous TiO_(2).The particle size of the chiral mesoporous TiO_(2) particles was about 200 nm,and it presented an obvious helical packing structure,which also showed a significant chiral correspondence effect.On the other hand,the morphology of achiral mesoporous TiO_(2) did not show the structure of helical stacking,but only showed the aggregation structure of some particles.Both chiral mesoporous TiO_(2) and achiral mesoporous TiO_(2) had two mixed crystal forms of anatase and rutile(Fig.4).The helical stacking structure of chiral mesoporous TiO_(2) introduced more defects into the catalyst,so that the contents of Ti^

关 键 词：手性介孔二氧化钛 可见光催化降解 罗丹明B 染料污染物 降解路径 废水处理 

分 类 号：O647[理学—物理化学]