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 Tioxo 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 À 1 , nearly three times as high as the phenolatelinked MOF glass with the highest BET surface area prior to this report.

Metal‐Organic Framework Glass Catalysts from Melting Glass‐Forming Cobalt‐Based Zeolitic Imidazolate Framework for Boosting Photoelectrochemical Water Oxidation

“…After melting quenching process, the residual solvent peak disappears. [48,49] Furthermore, hydrogen nuclear magnetic resonance ( 1 H NMR) was performed…”

Metal‐Organic Framework Glass Catalysts from Melting Glass‐Forming Cobalt‐Based Zeolitic Imidazolate Framework for Boosting Photoelectrochemical Water Oxidation

“…The C=O stretching vibration in Co‐ZIF‐62 at 1690 cm −1 is attributed to a small residual N,N‐dimethylformamide (DMF) solvent. After melting quenching process, the residual solvent peak disappears [48, 49] . Furthermore, hydrogen nuclear magnetic resonance ( 1 H NMR) was performed to determine the linker ratios of Im and bIm in the crystals and glass‐state materials (Figures S2, S3).…”

Multi‐stage Transformations of a Cluster‐Based Metal‐Organic Framework: Perturbing Crystals to Glass‐Forming Liquids that Re‐Crystallize at High Temperature

“…Conventional melt‐quenching method has produced a series of MOF glasses, mainly including some special zeolitic imidazolate frameworks and coordination polymers [4–8] . Other methods have also been developed to prepare MOF glasses, such as crystallization supression [9] and solution synthesis [10] . However, considering MOF glasses derived from crystalline MOFs with 3D network structure, none of them incorporates metal‐carboxylate cluster building units (Table S1), which accounts for a large part of the MOF database [11] .…”

“…[4][5][6][7][8] Other methods have also been developed to prepare MOF glasses, such as crystallization supression [9] and solution synthesis. [10] However, considering MOF glasses derived from crystalline MOFs with 3D network structure, none of them incorpo-rates metal-carboxylate cluster building units (Table S1), which accounts for a large part of the MOF database. [11] Though yet to be realized, MOF glasses and liquids composed of metal-carboxylate cluster building blocks could show much more complex chemical dynamics than those composed of single metal ions.…”