High‐Porosity Metal‐Organic Framework Glasses

Abstract We report a synthetic strategy to link titanium‐oxo (Ti‐oxo) clusters into metal‐organic framework (MOF) glasses with high porosity though the carboxylate linkage. A new series of MOF glasses was synthesized by evaporation of solution containing Ti‐oxo clusters Ti 16 O 16 (OEt) 32 , linkers, and m ‐cresol. The formation of carboxylate linkages between the Ti‐oxo clusters and the carboxylate linkers was confirmed by Fourier‐transform infrared (FT‐IR) spectroscopy. The structural integrity of the Ti‐oxo clusters within the glasses was evidenced by both X‐ray absorption near edge structure (XANES) and 17 O magic‐angle spinning (MAS) NMR. After ligand exchange and activation, the fumarate‐linked MOF glass, termed Ti‐Fum, showed a N 2 Brunauer–Emmett–Teller (BET) surface areas of 923 m 2 g −1 , nearly three times as high as the phenolate‐linked MOF glass with the highest BET surface area prior to this report.