四配位Co(Ⅱ)构建的螺旋配位聚合物:合成、结构和对CO2的光催化还原  

Helical Coordination Polymers Based on Tetra⁃coordinated Co(Ⅱ):Syntheses,Structures and Photocatalytic CO2 Reduction Reaction

作　　者：徐中轩 李立凤 白旭玲 XU Zhong-Xuan;LI Li-Feng;BAI Xu-Ling(School of Chemistry and Chemical Engineering,Zunyi Normal College,Zunyi,Guizhou 563002,China)

机构地区：[1]遵义师范学院化学化工学院,遵义563002

出　　处：《无机化学学报》2020年第8期1430-1436,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21761036);贵州省科学技术基金(No.20181181)资助项目。

摘　　要：在水热条件下,对映的乳酸衍生物(R)-4-(1-羧基乙氧基)苯甲酸((R)-H2CBA)和(S)-4-(1-羧基乙氧基)苯甲酸)((S)-H2CBA)分别与辅助配体1,3-双(2-甲基-1H-咪唑-1-基)苯(1,3-BMIB)以及Co(Ⅱ).反应,合成出一对结构新颖的金属-有机框架化合物{[Co((R)-CBA)(1,3-BMIB)]·H2O}n(1-D)和{[Co((S)-CBA)(1,3-BMIB)]·H2O}n(1-L)。单晶解析揭示在二维的1-D和1-L中,四配位的Co(Ⅱ).中心分别与乳酸衍生物(R)-H2CBA(或(S)-H2CBA)和/或1,3-BMIB一起构建出了3种不同结构的螺旋链。这对螺旋二维化合物在不同pH值的水中有一定的稳定性。紫外-可见吸收光谱显示1-D对420~650 nm范围的可见光有较强的吸收。进一步的Mott-Schottky测试表明1-D是典型的n型半导体。此外其较小的阻抗半径显示其有利于电子传输。在进一步的光催化实验中,1-D实现了光照条件下CO2转化为CO,反应平均速率为577.8μmol·g-1·h-1。A pair of homochiral coordination polymers,{[Co((R)-CBA)(1,3-BMIB)2]·H2 O}n(1-D,(R)-H2 CBA=(R)-4-(1-carboxyethoxy)benzoic acid,1,3-BMIB=1,3-bis(2-methyl-1 H-imidazol-1-yl)benzene)and{[Co((S)-CBA)(1,3-BMIB)2]·H2}n(1-L),were prepared by mixing Co2+,1,3-BMIB and lactic acid derivates(R)-H2 CBA/(S)-H2 CBA under hydrothermal condition,respectively.X-ray crystallography reveals there are three types of helical chains constructed by tetra-coordinated Co(Ⅱ)centers,1,3-BMIB and/or CBA2-ligands in complexes 1-D and 1-L.For unsaturated Co(Ⅱ)centers can act as catalytic active site,complex 1-D with high yield was further used for photo-catalytic research.Mott-Schottky measurements indicate that complex 1-D is a typical n-type semiconductor,while the UVVis spectrum confirmed that complex 1-D showed strong absorption in a range of 420~650 nm.Further more,complex 1-D has the small radius and the lowest resistance in charge transportation.Finally,complex 1-D realized photocatalytic reduction of CO2 to CO with an evolution rate of 577.8μmol·g-1·h-1 in the course of the experiment.CCDC:1963404,1-D:1963405,1-L.

关 键 词：配位聚合物 螺旋链 四配位Co(Ⅱ)中心 光催化CO2还原 

分 类 号：O614.812[理学—无机化学]