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The origin of the glass transition is still an open debate, especially for the new class of glasses, formed from metal-organic compounds. High-temperature in situ 2 H Nuclear Magnetic Resonance (NMR) experiments are performed on deuterated samples of ZIF-62 (Zn(C 3 H 4 N 2 ) 2-x (C 7 H 6 N 2 ) x , with x = 0.25 and x = 0.05), the prototypical metal-organic framework glass former. Using lineshape analysis, frequencies and angular amplitudes of oscillations of the imidazolate ring during heating up to the melt progressively increasing from ≈10 to 150 MHz, and from ≈5° to 25° are found. This behavior is compositionally dependent and points to the origin of the glass transition lying in organic linker movement, in a similar vein to that witnessed in some organics and contrary to the purely inorganic-based view of Metal-Organic Framework (MOF) glasses taken to date. This experimental approach shows the potential to elucidate the melting and/or decomposition process for a wide range of MOFs., (© 2023 The Authors. Small published by Wiley‐VCH GmbH.)

Crystalline materials have governed the development of hybrid organic-inorganic perovskites (HOIPs), giving rise to a variety of fascinating applications such as solar cells and optoelectronic devices. With increasing interest in non-crystalline systems, the glassy state of HOIPs has recently been identified. Here, the basic building blocks of crystalline HOIPs appear to be retained, though their glasses lack long-range periodic order. The emerging family of glasses formed from HOIPs exhibits diverse properties, complementary to their crystalline state. This mini review describes the chemical diversity of both three-dimensional and two-dimensional crystalline HOIPs and demonstrates how glasses are produced from these materials. Specifically, current achievements in melt-quenched glasses formed from HOIPs are highlighted. We conclude with our perspective on the future of this new family of materials., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The formation, and subsequent structural, thermal and adsorptive properties of single-component metal-organic framework crystal-glass composites (MOF-CGCs) are investigated. A series of novel materials exhibiting chemically identical glassy and crystalline phases within the same material were produced, where crystalline ZIF-62(Zn) was incorporated within an a g ZIF-62(Zn) matrix. X-ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of a g ZIF-62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed-metal (ZIF-62(Co)) 0.5 (a g ZIF-62(Zn)) 0.5 analogue. CO 2 gas adsorption measurements showed that the CO 2 uptakes of the MOF-CGCs were between those of the crystalline and glassy phases., (© 2021 Wiley-VCH GmbH.)

Metal-organic frameworks (MOFs) are a class of porous materials that show promise in the removal of toxic industrial chemicals (TICs) from contaminated airstreams, though their development for this application has so far been hindered by issues of water stability and the wide availability and low cost of traditionally used activated carbons. Here a series of three MOF-activated carbon composite materials with different MOF to carbon ratios are prepared by growing STAM-17-OEt crystals inside the commercially available BPL activated carbon. The composite materials display excellent water stability and increased uptake of ammonia gas when compared to unimpregnated carbon. Such properties make these composites very promising in the fields of air purification and personal protective equipment., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)