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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. [ABSTRACT FROM AUTHOR]

The structure of a new ZIF-8 polymorph with quartz topology (qtz) is reported. This qtz-[Zn(mIm)2] phase was obtained by mechanically amorphising crystalline ZIF-8, before heating the resultant amorphous phase to between 282 and 316 °C. The high-temperature phase structure was obtained from powder X-ray diffraction, and its thermal behaviour, CO2 gas sorption properties and dye adsorption ability were investigated. [ABSTRACT FROM AUTHOR]

Glasses formed by the melt quenching of metal–organic frameworks (MOFs) are the first new category of glass since metallics in the 1970s, and have begun to redistribute attention in the MOF field away from the crystalline state. Those formed to date are, however, relatively dense and so proposed interest focuses mainly on their physical properties. Here, we suggest routes to incorporate porosity into the glasses, borrowing from both inorganic and organic polymer science. We then speculate on the future adsorptive applications of these materials. [ABSTRACT FROM AUTHOR]

Here we present efficient and scalable mechanochemical formation of hybrid organic–inorganic perovskites of the form [TPrA][M(dca)3] (M = Mn2+, Co2+) and the subsequent formation of their bulk melt-quenched glasses. In situ X-ray diffraction reveals direct, facile, and almost instantaneouos formation of both crystalline materials, while slow cooling limits recrystallisation in glasses. The glasses show good stability to acidic and basic aqueous solutions and display higher carbon dioxide uptakes than their crystalline precursors. [ABSTRACT FROM AUTHOR]

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 agZIF‐62(Zn) matrix. X‐ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of agZIF‐62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed‐metal (ZIF‐62(Co))0.5(agZIF‐62(Zn))0.5 analogue. CO2 gas adsorption measurements showed that the CO2 uptakes of the MOF‐CGCs were between those of the crystalline and glassy phases. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs) can be melt-quenched to form glasses. Here, we present an alternative route to glassy ZIFs via mechanically induced amorphisation. This approach allows various glassy ZIFs to be produced in under 30 minutes at room temperature, without the need for melt-quenching. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) are promising materials for many potential applications, spacing from gas storage to catalysis. However, the powder form they are generally made of is not suitable, mainly because of the low packing density. Powder compaction is therefore necessary, but also challenging because of its typical mechanical fragility. Indeed, generally, MOF powders undergo irreversibly damages upon densification processes, for example partially or totally loosing microporosity and catalytic activity. In this work, we have deeply studied the compaction effects on the flexible Cu(II)‐based MOF STAM‐17‐OEt (Cu(C10O5H8) ⋅ 1.6 H2O), whose chemical composition is close to that of HKUST‐1, obtaining that, by contrast, STAM‐17‐OEt is extremely suitable for mechanical compaction processes with pressures up to 200 MPa, which increase its packing density and its catalytic activity, and then also preserve the characteristic porosity, flexibility and water stability of STAM‐17‐OEt. The results are supported by many experimental techniques including EPR spectroscopy, PXRD diffraction, CO2 isotherms studies and catalytic tests. [ABSTRACT FROM AUTHOR]

Metal–organic framework crystal–glass composites (MOF CGCs) have previously been formed by embedding crystalline MIL-53(Al) within a ZIF-62 glass (agZIF-62) matrix. Here we highlight thermal stability considerations in the formation of MOF CGCs, and subsequently report the synthesis of two novel MOF CGCs, by incorporating MIL-118 and UL-MOF-1 within agZIF-62. These new materials, alongside the prototypical MOF CGC, formed using MIL-53(Al), were studied using scanning electron microscopy, powder X-ray diffraction, and gas sorption techniques. The gas uptake in composites formed from MIL-118C and UL-MOF-1 is largely dominated by the agZIF-62 matrix, suggesting that to improve the porosity of the MOF CGC, the matrix porosity must be improved, or a percolation threshold must be overcome. [ABSTRACT FROM AUTHOR]

Here we demonstrate the synthesis and structural characterisation of a novel copper MOF: STAM-NMe2, developed using the linker 5-dimethylamino isophthalic acid. The material is a member of the STAM series of MOFs, with a Kagome lattice structure and contains two types of pore system. The structure was investigated using single crystal X-ray diffraction, variable temperature powder X-ray diffraction was used to determine the thermal stability of the MOF, and nitrogen BET adsorption was employed to determine the porosity of the material. [ABSTRACT FROM AUTHOR]

Here we demonstrate the synthesis and structural characterisation of a novel copper MOF: STAM-NMe2, developed using the linker 5-dimethylamino isophthalic acid. The material is a member of the STAM series of MOFs, with a Kagome lattice structure and contains two types of pore system. The structure was investigated using single crystal X-ray diffraction, variable temperature powder X-ray diffraction was used to determine the thermal stability of the MOF, and nitrogen BET adsorption was employed to determine the porosity of the material. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A study into the disassembly and organisation steps of the ADOR process has been undertaken through in situ Pair Distribution Function (PDF) analysis. Three aqueous systems (water, 6 M HCl and 12 M HCl) were introduced to a parent zeolite germanosilicate UTL in a cell. Hydrolysis could be clearly seen when UTL was exposed to water over a period of 8 h, forming the disorder layered material, IPC-1P. In hydrochloric acid, the hydrolysis step is too quick to observe and a Ge–Cl containing species could be seen. In 6 M HCl, the rearrangement of the interlayer region began after an induction period of 8 h, with the process still occurring after 15 h. In 12 M HCl, the rearrangement appears to have come to an end after only 6 h. [ABSTRACT FROM AUTHOR]