Solvothermal preparation of copper(II) porphyrin-sensitized mesoporous TiO2 composites: enhanced photocatalytic activity and stability in degradation of 4-nitrophenol
作者:Xiao Liu、Mimi Yu、Zengqi Zhang、Xin Zhao、Jun Li
DOI:10.1007/s11164-015-2349-y
日期:2016.6
Four new copper(II) porphyrins CuPp(1, 2, 3, 4) with a different number of peripheral ester groups were synthesized and used to sensitize the mesoporous TiO2 under solvothermal condition, and accordingly, four mesoporous CuPp(1, 2, 3, 4)/TiO2 composites were obtained. These composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, BET nitrogen adsorption–desorption isotherms (BET), UV–vis diffuse reflectance spectroscopy (UV–vis-DRS), and Fourier-transform infrared spectroscopy (FT-IR). The results showed the crystal structure and morphology of mesoporous TiO2 were not affected by the porphyrin existence on its surface. The photocatalysis properties of mesoporous TiO2 and CuPp(1, 2, 3, 4)/TiO2 have been evaluated by conducting the photocatalytic degradation of 4-nitrophenol (4-NP) under visible-light irradiation, and the result showed their higher photocatalytic activities and the order is: CuPp(4)/TiO2 > CuPp(3)/TiO2 > CuPp(2)/TiO2 > CuPp(1)/TiO2 ≫ TiO2. The probable reasons are their large surface area and different number of peripheral groups in CuPp, which separate electron–hole pairs efficiently. The repetition test of CuPp(1, 2, 3, 4)/TiO2 composites demonstrated that they still maintained superior photocatalytic activity over six recycles.
合成了四种具有不同数量外围酯基的新型
铜(II)
卟啉 CuPp(1、2、3、4),并在溶热条件下将其用于介孔
二氧化钛的敏化,从而获得了四种介孔 CuPp(1、2、3、4)/
二氧化钛复合材料。这些复合材料的表征方法包括 X 射线衍射、扫描电子显微镜、透射电子显微镜、BET 氮吸附-解吸等温线(BET)、紫外-可见漫反射光谱(UV-vis-DRS)和傅立叶变换红外光谱(FT-IR)。结果表明,介孔
二氧化钛的晶体结构和形貌不受其表面
卟啉存在的影响。通过在可见光照射下对 4-
硝基苯酚(4-NP)进行光催化降解,评估了介孔
二氧化钛和 CuPp(1, 2, 3, 4)/TiO2 的光催化性能:CuPp(4)/TiO2 > CuPp(3)/TiO2 > CuPp(2)/TiO2 > CuPp(1)/TiO2 ≫ TiO2。可能的原因是它们的比表面积大,而且 CuPp 中外围基团的数量不同,能有效分离电子-空穴对。对 CuPp(1、2、3、4)/TiO2 复合材料的重复测试表明,它们在六次循环后仍能保持优异的光催化活性。