基于2,5-二甲氧基对苯二甲酸和咪唑衍生物的半导体型钴-配合物的合成、结构和光催化性质

Semiconductive Co(Ⅱ)-complexes based on 2,5-dimethoxyterephthalic acid and imidazole derivatives:synthesis,crystal structures and photo-catalytic poperties

在2,5-二甲氧基对苯二甲酸(H_(2)DTA)存在下,咪唑衍生物1,1’-(5-甲基-1,3-亚苯基)双(2-甲基-1H-咪唑)(1,3-MPBMI)和1,3-二(1H-咪唑-1-基)苯(1,3-DIB)作为配体通过与Co^(2+)水热反应,得到了两个配合物[Co(DTA)(1,3-MPBMI)]_(n)(1)和[Co(DTA)(1,3-DIB)(H_(2)O)]_(n)(2)。单晶结构分析揭示两个配合物都是由二维层构建出的三维超分子化合物。粉末衍射则揭示配位物1和2在通常的有机溶剂和水中都非常稳定。进一步的紫外-可见光谱、Mott-Schottky和电化学阻抗(ESI)测试显示配合物1和2是典型的n-型半导体,具有较低的电荷传输阻抗值。光催化实验中,配合物1和2可催化降解染料亚甲基蓝。

In the presence of 2,5-dimethoxyterephthalic acid(H_(2)DTA),complexes[Co(DTA)(1,3-MPBMI)]_(n)(1)and[Co(DTA)(1,3-DIB)(H_(2)O)]_(n)(2)were synthesized by using 1,1’-(5-methyl-1,3-phenylene)bis(2-methyl-1H-imidazole)(1,3-MPBMI)and 1,3-di(1H-imidazol-1-yl)benzene(1,3-DIB)as linkers to react with Co(Ⅱ)ions under hydrothermal condition.Single crystal structural analysis reveals that 1 and 2 are all three-dimentional(3D)supramolecular complexes packed by two-dimentional(2D)frameworks.The powder X-ray diffraction further firms that complexes 1 and 2 are stable in water under UV light.Moreover,the UV/vis spectra,Mott-Schottky measurements and electrochemical impedance spectroscopy(EIS)demonstrated that 1 and 2 are typical n-type semiconductors with low resistance in charge transportation.Finally,photocatalytic tests indicated the complex 1 and 2 have catalytic activity for the degradation of methylene blue(MB)in water.