蔺波涛,施冬梅(军械工程学院,河北 石家庄 050003)
Sn掺杂TiO2/ACF复合材料的制备、表征及光催化性能
蔺波涛,施冬梅
(军械工程学院,河北 石家庄 050003)
摘要:以Ti(OC4H9)4为前体,SnCl4为Sn源,采用胶溶-回流法制备了Sn掺杂的TiO2,利用浸渍提拉法将其负载到活性炭纤维(ACF)表面,并运用SEM、XRD、XPS、DRS等手段对TiO2/ACF复合材料进行表征,考察了复合材料光催化降解气相甲醛的性能。研究结果表明,Sn元素掺入TiO2晶格中,有利于抑制TiO2晶粒的生长,促进TiO2由锐钛矿型向金红石型的转化,光吸收范围发生一定程度红移;HNO3的用量为0.015mol、掺锡量为6%、负载两层的TiO2/ACF-50复合材料在紫外光照射下对甲醛的去除率复合材料可达85.2%,而在可见光下仅为65.3%。
关键词:TiO2/ACF复合材料;吸附;催化剂;锡掺杂
第一作者及联系人: 蔺波涛(1987—), 男, 硕士研究生。 E-mail linbotao 2126@126.com。
Preparation and characterization of Sn doped TiO2/ACF photocatalytic composite material
LIN Botao,SHI Dongmei
(Ordnance Engineering College,Shijiazhuang 050003,Hebei,China)
Abstract:Sn/TiO2was prepared with Ti(OC4H9)4and SnCl4by peptization-refluxing method.TiO2was loaded to the surface of ACF by the use of dip-coating method.TiO2/ACF was characterized by Scanning Electron Microscopy,X-ray Diffraction,X-ray Photoelectron Spectroscopy and UV-VISDiffuse Reflectance Spectroscopy,and the degradation of CH2O was investigated. When Sn was incorporated into TiO2,the growth of TiO2grains was inhibited and the conversion of TiO2was promoted from anatase to rutile. The range of light absorbed by TiO2was redshift. When 0.015 mol HNO3were used and 6% Sn were doped content,the removal rate of CH2O was 85.2 percent by two layer TiO2/ACF-50 under UV irradiation,while that of only 65.3 percent was obtained under the visible light.
Key word:TiO2/ACF composites; adsorption; catalysis; Sn doped
光催化氧化技术具有氧化能力强、光催化效率高、无二次污染等优点。TiO2作为一种应用最广泛的光催化剂,能够在紫外光的照射下催化降解大部分有机污染物[1]。目前关于TiO2光催化剂的研究大部分都是围绕如何克服其量子效率较低、带隙能较高(3.2eV)、不易回收等缺陷展开的,而当前TiO2的改性方法有半导体耦合法、离子掺杂法、贵金属沉积法和表面光敏化法等[2]。离子掺杂法由于操作简单、提高TiO2光催化效果较好,成为了TiO2改性的一种常用方法。
Sn是一种良好的金属离子掺杂剂,曾在ZnO、TiO2等半导体光催化剂的掺杂改性中具有较好的效果而引起广泛关注[3]。适量Sn的掺入,使TiO2的晶体内质点排列周期性受到破坏,导致点阵结构的周期势场发生畸变,引起晶格缺陷,一方面导致氧原子逃离TiO2晶格,氧空位的出现形成光生电子的捕获中心,有效抑制了光生电子-空穴对的复合;……