铜离子掺杂纳米二氧化钛催化剂的改性研究  

Research on the Modification of Copper Ions Doped Nano Titanium Dioxide Catalyst

作　　者：徐大鹏[1] 张松[1] 杨巍[1] 

机构地区：[1]西安工业大学材料与化工学院,西安710021

出　　处：《西安工业大学学报》2017年第6期431-437,共7页Journal of Xi’an Technological University

基　　金：国家自然科学基金(11504284);陕西省教育厅专项科研计划项目(16JK1377)

摘　　要：针对纯纳米TiO_2粉末带隙能宽(约为3.2eV),对太阳光利用率较低的问题.文中通过对液料等离子喷涂的前驱物-钛酸丁酯和乙醇溶液中添加掺杂成分Cu(NO3)2·6H2O制备了掺杂粉末.利用透射电镜(TEM)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、紫外-可见-近红外分光光度计(UV-Vis)和荧光分光光度计(PL)分析了掺杂对TiO_2样品的形貌、晶体结构及平均粒径、表面成分和元素价态、本征吸收带及电子结构和光学特性的影响.利用光催化降解甲基橙来评价铜离子掺杂样品的光催化活性.结果表明:铜离子掺杂纳米TiO_2粉末形貌呈球形或近球形,粒径分布范围为10~60nm,少量的铜离子掺杂使TiO_2粒径分布均匀,且粉末的粒径有所减小;制备的粉末均为锐钛矿和金红石相的混合晶体,且随着掺杂含量的增加,锐钛矿相含量呈减小的趋势;掺杂纳米TiO_2粉末中含有O、Ti、C以及Cu元素,Cu元素的价态不变,Ti 2p区由2p3/2和2p1/2双峰组成,Ti元素仍为+4价;掺杂铜离子的TiO_2相比于未掺杂的TiO_2的本征吸收带边均发生了明显的红移.随着催化剂中铜离子掺杂含量增加,甲基橙的降解率均呈现出先增加后减少的趋势,0.2%的Cu2+掺杂TiO_2粉末对甲基橙的光催化活性最好,为纯TiO_2粉末降解率的1.40倍.Titanium dioxide（TiO_2）nanopowders which have wide band gap（about 3.2eV）can not better utilize sunlight.To overcome the disadvantage,TiO_2 nanopowders weremodified by doping Cu（NO_3）_2·6H_2O in the spraying precursor of the solution of titanium tetra-tert-butoxide and alcohol.The morphology,crystal structure and average grain diameter,surface component and element valency,intrinsic absorption band,electronic structure and optical characteristics of the prepared TiO_2 samples were characterized by using transmission electron microscopy（TEM）,X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,UV-VIS-NIR spectrophotometer（UV-Vis）and fluorescence spectrophotometer（PL）.The photocatalytic activity of the samples at different copper ions doping concentrations in photocatalytic degradation of methyl orange was discussed.The main conclusions are as follows.The prepared TiO_2 nanopowders are spherical or near spherical with the grain diameter ranging from 10 to 60nm.The small quantity of copper ions doped TiO_2 nanopowders have smaller particle size and uniform distribution.The prepared powders are the mixed crystals of anatase phase and rutile phase.The contents of anatase phase decrease with an increase in the doping contents.There are O,Ti,C and Cu in the doped TiO_2 nanopowders.The valences of Cu are invariant.Ti 2p region is composed of2p3/2peak and 2p1/2 peak and Ti element is still of quadravalence.The intrinsic absorption band of the doped TiO_2 nanopowders shifts into the infrared region compared with the TiO_2 nanopowders without doping.The degradation rate of methyl orange increases at first and then decreases with an increase in the content of copper ions in catalyst.The photocatalytic activity of TiO_2 powders doped with 0.2%Cu2＋to methyl orange is optimal,which is 1.40 times the degradation rate of the pure TiO_2.

关 键 词：等离子喷涂 二氧化钛 纳米粉末 铜离子掺杂 光催化 

分 类 号：O643.36[理学—物理化学] TB383.1[理学—化学]