铁、铜双节点金属有机骨架合成及光催化降解罗丹明B机制研究

Study on Synthesis of Iron-Copper Tow-Node Metal Organic Framework and Mechanism of Photodegrading Rhodamine B

采用三氯化铁、氯化铜和酒石酸为原料,通过水热合成法合成了一种双金属节点的金属有机骨架,并命名为DM-MOF。利用X射线衍射、傅里叶红外光谱和扫面电镜对其晶体结构和微观形貌进行了研究。随后用于光催化降解罗丹明B(RhB),通过不同催化体系、催化剂投加量和反应初始p H考察了DM-MOF的催化性能。最后还通过不同自由基猝灭实验分析了RhB的降解机制。结果表明:DM-MOF具有稳定的晶体结构,在50 min内对RhB的去除率能够达到98.8%,并且能够在较宽的p H范围内(3.0~7.0)稳定工作。自由基淬灭实验表明,降解RhB的主要物质是羟基自由基(·OH),并且35%的·OH由光生空穴(h+)生成,65%是由过氧化氢(H2O2)分解产生。

As a kind highly efficient catalyst,metal-organic frameworks have been widely used in the field of environmental modification.In this study,a metal organic framework with tow-node was synthesized from ferric chloride,cupric chloride and tartaric acid by solvothermal method,and named as DM-MOF.The crystal structure and morphology were studied by X-ray diffraction,Fourier transform infrared and scanning electron microscopy.Subsequently,it was used to photodegrade Rhodamine B(RhB).The catalytic performance of DM-MOF was investigated by different catalyst,catalyst dosage and initial pH.Finally,the degradation mechanism of RhB was analyzed by different radicals scavenging reactions.The results showed that DM-MOF had a stable crystal structure.The removal efficiency of RhB reached 98.8%within 50 min,and it could work stably in a wide pH range(3.0~7.0).Radical scavenging reactions showed that the hydroxyl radicals(·OH)was main substance to degrade RhB,and 35%of·OH was produced by holes(h+),and 65%was produced by decomposition of hydrogen peroxide(H2 O2).