三唑−吡啶羧酸铜配合物微晶光催化降解有机染料的活性与机理

Synthesis and photocatalytic activities of Cu(Ⅱ)complex micro-crystals derived from trizole-pyridyl carboxylic acid

以CuCl_(2)∙2H_(2)O和三唑−吡啶羧酸(Htpa)为原料,在DMF和甲醇混合溶剂中通过溶剂挥发法制备了配合物[Cu_(2)(tpa)_(2)(OH)]_(n)的微晶.利用红外光谱、扫描电子显微镜、X射线粉末衍射和固体紫外−可见漫反射光谱对铜配合物微晶进行了表征.在可见光照射下,用[Cu_(2)(tpa)_(2)(OH)]n/H_(2)O_(2)体系光催化降解碱性品红和罗丹明B染料,并且对两种染料的降解过程作动力学模拟.结果显示,[Cu_(2)(tpa)_(2)(OH)]_(n)/H_(2)O_(2)催化体系对碱性品红和罗丹明B均有良好的光催化降解能力,可见光照射90 min时,碱性品红的降解率达到84.0%,可见光照射25 min时,罗丹明B的降解率达到96.3%.动力学研究表明,碱性品红和罗丹明B的降解过程均符合准一级反应动力学模型,碱性品红和罗丹明B降解过程的表观速率常数k分别为2.030×10^(−2)min^(−1)和1.246×10^(−1)min^(−1).最后,讨论了[Cu_(2)(tpa)_(2)(OH)]n/H_(2)O_(2)体系光催化降解有机染料的机理.

Micro-crystals of complex[Cu_(2)(tpa)_(2)(OH)]_(n) were prepared using CuCl_(2)∙2H_(2)O and trizole-pyridyl carboxylic acid(Htpa)as raw material in DMF/methanol solvent by a solvent volatilization method.The synthesized Cu(Ⅱ)complex micro-crystals were characterized by infrared spectroscopy,scanning electron microscope,X-ray powder diffraction and UV-Vis diffuse reflection spectroscopy.The photocatalytic system consisting of[Cu_(2)(tpa)_(2)(OH)]_(n) and H_(2)O_(2) was used to degrade the alkaline fuchsin and rhodamine B dyes under visible light,and the degradation process of alkaline fuchsin and rhodamine B was simulated by kinetic models.The results showed that[Cu_(2)(tpa)_(2)(OH)]_(n)/H_(2)O_(2) catalytic system exhibited good photocatalytic activities for the degradation of alkaline fuchsin and rhodamine B dyes.The degradation efficiency of alkaline fuchsin was up to 84.0%after reacting for 90 min,while the degradation efficiency of rhodamine B was up to 96.3%after reacting for 25 min.The reaction kinetic study suggested that the photodegradation processes of alkaline fuchsin and rhodamine B were in accordance with the pseudo-first-order kinetic model.The rate constants(k)of alkaline fuchsin and rhodamine B are 2.030×10^(−2) min^(−1) and 1.246×10^(−1) min^(−1),respectively.Finally,the mechanism of photocatalytic degradation of organic dyes by[Cu_(2)(tpa)_(2)(OH)]_(n)/H_(2)O_(2) system was discussed.