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 4000 m2 g−1 that persists after immersion in water. These properties are not accessible for the isostructural phases made from the separate single linkers. Zwei Linker mit äquivalenter Konnektivität, aber deutlich verschiedener Drehbarkeit sind Komponenten des strukturell und chemisch stabilen Metall‐organischen Gerüsts [Zr6O4(OH)4(L1)2.6(L2)0.4]⋅(Solvens)x. Diese Eigenschaftskombination lässt sich nicht mit isostrukturellen Phasen erreichen, die nur einen Linker enthalten. Das Zirconium‐organische Gerüst zeichnet sich durch dreidimensionale Kanäle und eine große BET‐Oberfläche aus (4184 m2 g−1).