High Proton Conductivity by a Metal–Organic Framework Incorporating Zn8O Clusters with Aligned Imidazolium Groups Decorating the Channels

作者：Susan Sen, Nisanth N. Nair, Teppei Yamada, Hiroshi Kitagawa, Parimal K. Bharadwaj · 发表于：Journal of the American Chemical Society · 年份：2012 · DOI：10.1021/ja3076378 · 被引用次数：281 · 研究领域：Metal-Organic Frameworks: Synthesis and Applications、Fuel Cells and Related Materials、Magnetism in coordination complexes

A novel metal-organic framework, [{(Zn(0.25))(8)(O)}Zn(6)(L)(12)(H(2)O)(29)(DMF)(69)(NO(3))(2)](n) (1) {H(2)L = 1,3-bis(4-carboxyphenyl)imidazolium}, has been synthesized under solvothermal conditions in good yield. It shows a Zn(8)O cluster that is coordinated to six ligands and forms an overall three-dimensional structure with channels along the crystallographic a and b axes. The imidazolium groups of the ligand moiety are aligned in the channels. The channels are not empty but are occupied by a large number of DMF and water molecules. Upon heating, these solvent molecules can be removed without breakdown of the overall structure of the framework as shown by variable-temperature powder X-ray diffraction patterns. Of great interest is the fact that the compound exhibits high proton conductivity with a low activation energy that is comparable to those of Nafion presently used in fuel cells.