球形Cu_(2)O@HP-β-CD合成、表征及类芬顿去除水中亚甲基蓝的研究

Synthesis,Characterization of Spherical Cu_(2)O@HP-β-CD and the Fenton-Like Catalytic Removal of Methylene Blue in Aqueous Solution

利用液相沉淀法制备Cu_(2)O@HP-β-CD,通过XRD、SEM、FT-IR对Cu_(2)O@HP-β-CD的结构进行表征,并研究其对亚甲基蓝(MB)的类芬顿催化降解性能。XRD图谱显示样品的衍射峰为纯Cu_(2)O,HP-β-CD与Cu摩尔比为1:1时样品SEM形貌为500 nm,大小均一的球形。Cu_(2)O@HP-β-CD类芬顿体系降解MB的实验结果表明,当HP-β-CD与Cu摩尔比为1:1,加入浓度为20 mmol/L的H_(2)O_(2),100 min时MB去除率达到96.1%。相同条件下,液相法单一合成的Cu_(2)O的MB去除率为54.4%;Cu_(2)O@HP-β-CD的一级动力学反应速率常数为0.02776 min^(-1),高于Cu_(2)O的反应速度常数(0.0074 min^(-1))。Cu_(2)O@HP-β-CD的自由基捕获实验表明了·OH在催化降解过程中起主要作用。

Cu_(2)O@HP-β-CD was prepared by liquid-phase precipitation,and the structure of Cu_(2)O@HP-β-CD was characterized by XRD,SEM and FT-IR,and its Fenton-like catalytic degradation performance of methylene blue(MB)was investigated.XRD patterns show that the diffraction peak of the sample is pure Cu_(2)O,and the SEM morphology is 500 nm with homogeneous spherical size when the molar ratio of HP-β-CD to Cu is 1:1.The results of the Fenton-like degradation of MB by Cu_(2)O@HP-β-CD show that the removal rate of MB reaches 96.1%at 100 min when the molar ratio of HP-β-CD to Cu is 1:1 and the concentration of H_(2)O_(2)added is 20 mmol/L.Under the same conditions,the removal rate of MB is 54.4%when Cu_(2)O is synthesized singly by the liquid-phase method.A first-order kinetic reaction rate constant of Cu_(2)O@HP-β-CD is 0.02776 min^(-1),which is higher than that of Cu_(2)O(0.0074 min^(-1)).And the radical capture experiments of Cu_(2)O@HP-β-CD demonstrate that·OH playes a major role in the catalytic degradation process.