2D metal–organic frameworks: Syntheses, structures, and electrochemical properties

• Anionic or neutral layered coordination networks with secondary functional group.
• One-dimensional channels along the stacking directions of the layered networks.
• Novel secondary building unit of cobalt-carboxylate clusters.
• Characteristic low frequency impedance plots as electrode materials.

Two new 2D metal–organic framework materials, [Cu(Br2BDC)2](HTEA)2 (1) and [Co2(Br2BDC)(HCOO)2(DMF)2] (2) (Br2BDC = 2,5-dibromoterephthalate, DMF = dimethylformamide, TEA = triethylamine), have been synthesized through solvothermal reactions. Compound 1 consists of anionic layered networks balanced with HTEA+ cations located between the layers. The layered network of 1 is a uninodal 4-connected net in which copper ions act as the uninodals and the Br2BDC ligand as the linkers. The structure of 2 is a neutral 2D coordination network containing hexagonal rings of clusters formed by six CoO6 octahedra. The topology of the 2D network in 2 is a uninodal 6-connected net with the clusters as the nodals. In both compounds, the stacking of the layers forms one-dimensional channels. The electrochemical performance of compounds 1 and 2 was also studied using cyclic voltammetry and electrochemical impedance spectroscopy.

Neutral to anionic 2D networks constructed from 2,5-dibromoterepthalicate and transitional metal ions can stack to form one-dimensional channels. Impedance plots of electrodes of these solids confirm the formation of one-dimensional channels.Figure optionsDownload as PowerPoint slide