PMOV_2/PANI/TiO_2复合材料的制备及光催化性能

Preparation of composite PMOV_2/PANI/TiO_2 and photocatalytic performance

以(NH4)2S2O8为氧化剂,运用化学氧化聚合法在TiO2颗粒表面包覆聚苯胺薄膜,通过静电自组装方法制备了复合光催化材料PMOV2/PANI/TiO2,采用傅里叶变换红外光谱(FT-IR)、紫外-可见吸收光谱(UV-Vis)、X-射线粉末衍射(XRD)、热分析(TG-DTG)、扫描电子显微镜(SEM)等手段对其组成、结构及形貌等进行了表征。结果表明,复合材料具有锐钛矿晶型结构,颗粒分布较均匀,结构也较规整,平均粒径约为68.53nm。聚苯胺敏化拓宽了TiO2的光谱响应范围,复合材料在紫外和可见光区都有较强的吸收,提高了光能的利用率和光生载流子的分离效率。在光催化降解染料甲基紫研究中,该复合材料表现出较好的光催化性能。其活性明显高于市售P25(TiO2),PANI/TiO2,PMOV2和PA-NI,降解率达97.1%。

Composite photocalalytic materials PMOV2/PANI/TiO2 was prepared by the chemical oxidative poly- merization with （NH4）2 S2 08 as oxidant to form polyaniline-wrapped TiO2 particles and then by an electrostatic assembly of PMOV2. The phase structures, chemical composition, optical absorption properties and surface physicochemical properties of the comositewere Characterized by Fourier transform infrared（FT-IR） spectrum,UV-visible absorption spectrum（UV- Vis）,X-ray diffraction（XRD） , thermal-analysis（TG-DTG） and scanning electron microscopy（SEM）. The results showed that the composite had anatase crystalline structure, an orderly distribution of particles and good structure, and the particle size were ca 68. 53nm. The sensitizing effect of PANI can improve the light response of TiO2 and enhanced the separation efficiency of electron and hole pairs which in turn promoted the photocatalytic ability of the composite. The photocatalytic activities of the composite were tested by photocatalytic degradation of the dyes, for example,methyl violet. Results showed that this composite had fine photocatalytic activities for many dyes,and the activity was higher than that of Degussa P25 （ TiO2 ）, PANI/TiO2, PMOV2 and PANI, the decoloration rate of methyl violet achieved 97.0 %.