Chemical and Structural Stability of Zirconium-based Metal-Organic Frameworks with Large Three-Dimensional Pores by Linker Engineering

The synthesis of metal-organic frameworks with large three-dimensional channels that are permanently porous and chemically stable offers new opportunities in areas such as catalysis and separation. Two linkers (L1=4,4,4,4-([1,1-biphenyl]-3,3,5,5-tetrayltetrakis(ethyne-2,1-diyl)) tetrabenzoic acid, L2=4,4,4,4-(pyrene-1,3,6,8-tetrayltetrakis(ethyne-2,1-diyl))tetrabenzoic acid) were used that have equivalent connectivity and dimensions but quite distinct torsional flexibility. With these, a solid solution material, [Zr6O4(OH)(4)(L1)(2.6)(L2)(0.4)](solvent)(x), was formed that has three-dimensional crystalline permanent porosity with a surface area of over 4000m(2)g(-1) that persists after immersion in water. These properties are not accessible for the isostructural phases made from the separate single linkers.