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The capability of materials to interconvert between different phases provides more possibilities for controlling materials' properties without additional chemical modification. The study of state-changing microporous materials just emerged and mainly involves the liquefication or amorphization of solid adsorbents into liquid or glass phases by adding non-porous components or sacrificing their porosity. The material featuring reversible phases with maintained porosity is, however, still challenging. Here, we synthesize metal-organic polyhedra (MOPs) that interconvert between the liquid-glass-crystal phases. The modular synthetic approach is applied to integrate the core MOP cavity that provides permanent microporosity with tethered polymers that dictate the phase transition. We showcase the processability of this material by fabricating a gas separation membrane featuring tunable permeability and selectivity by switching the state. Compared to most conventional porous membranes, the liquid MOP membrane particularly shows the selectivity for CO2 over H2 with enhanced permeability. The capability of materials to interconvert between phases enables greater control over properties without additional chemical modification but can result in a sacrifice of porosity. Here, the authors synthesize metal-organic polyhedra that interconvert between the liquid-glass-crystal phases and develop a membrane with enhanced porosity and CO2 selectivity. [ABSTRACT FROM AUTHOR]

Metal-organic network-forming glasses are an emerging type of material capable of combining the modular design and high porosity of metal-organic frameworks and the high processability and optical transparency of glasses. However, a generalizable strategy for achieving both high porosity and high glass-forming ability in modularly designed metal-organic networks has yet to be developed. Herein, we develop a series of aluminum alkoxide glasses and monoliths by linking aluminum-oxo clusters with alcohol linkers. A bulky monodentate alcohol modulator is introduced during synthesis and act as both network plasticizer and pore template, which can be removed by the subsequent solvent exchange to give gas accessible pores. Glasses synthesized with the modulator template exhibit well-defined glass transitions in their as-synthesized form and high surface areas up to 500 m2/g after activation, making them among the most porous glassy materials. The aluminum alkoxide glasses also have optical transparency and fluorescent properties, and their structures are elucidated by pair-distribution functions, spectroscopic and compositional analysis. These findings could significantly expand the library of microporous metal-organic network-forming glasses and enable their future applications. By linking in situ formed aluminium-oxo clusters and multi-dentate alcohol linkers in the presence of a bulky pore-templating modulator, the authors synthesized porous and transparent aluminium alkoxide network-forming glasses. [ABSTRACT FROM AUTHOR]

Dynamically responsive materials, capable of reversible changes in color appearance and/or photoemission upon external stimuli, have attracted substantial attention across various fields. This study presents an effective approach wherein switchable modulation of photochromism and ultralong phosphorescence can be achieved simultaneously in a zero-dimensional organic-inorganic halide hybrid glass doped with 4,4´-bipyridine. The facile fabrication of large-scale glasses is accomplished through a combined grinding-melting-quenching process. The persistent luminescence can be regulated through the photochromic switch induced by photo-generated radicals. Furthermore, the incorporation of the aggregation-induced chirality effect generates intriguing circularly polarized luminescence, with an optical dissymmetry factor (glum) reaching the order of 10–2. Exploiting the dynamic ultralong phosphorescence, this work further achieves promising applications, such as three-dimensional optical storage, rewritable photo-patterning, and multi-mode anti-counterfeiting with ease. Therefore, this study introduces a smart hybrid glass platform as a new photo-responsive switchable system, offering versatility for a wide array of photonic applications. Dynamically responsive afterglow materials are typically fabricated as single crystals, polymers or powders. Here, the authors use zero-dimensional metal halides and organic dopants to develop photochromic glasses for diverse optical applications. [ABSTRACT FROM AUTHOR]

By combining the porosity of crystalline metal-organic frameworks (MOFs) with the unique processability of the liquid state, melt-quenched MOF glasses offer exciting opportunities for molecular separation. However, progress in this field is limited by two factors. Firstly, only very few MOFs melt at elevated temperatures and transform into stable glasses upon cooling the corresponding MOF liquid. Secondly, the MOF glasses obtained thus far feature only very small porosities and very small pore sizes. Here, we demonstrate solvent-assisted linker exchange (SALE) as a versatile method to prepare highly porous melt-quenched MOF glasses from the canonical ZIF-8. Two additional organic linkers are incorporated into the non-meltable ZIF-8, yielding high-entropy, linker-exchanged ZIF-8 derivatives undergoing crystal-to-liquid-to-glass phase transitions by thermal treatment. The ZIF-8 glasses demonstrate specific pore volumes of about 0.2 cm3g–1, adsorb large amounts of technologically relevant C3 and C4 hydrocarbons, and feature high kinetic sorption selectivities for the separation of propylene from propane. The canonical metal-organic framework ZIF-8 does not melt and form a glass. Here, authors incorporated two additional organic linkers into ZIF-8 to generate meltable derivatives which can be transformed into highly porous glasses by melt-quenching. [ABSTRACT FROM AUTHOR]

Over the last decade, perovskite solar cells (PSCs) have drawn extensive attention owing to their high power conversion efficiency (single junction: 26.1%, perovskite/silicon tandem: 33.9%) and low fabrication cost. However, the short lifespan of PSCs with initial efficiency still blocks their practical applications. This operational instability may originate from the intrinsic and extrinsic degradation of materials or devices. Although the lifetime of PSCs has been prolonged through component, crystal, defect, interface, encapsulation engineering, and so on, the systematic analysis of failure regularity for PSCs from the perspective of materials and devices against multiple operating stressors is indispensable. In this review, we start with elaboration of the predominant degradation pathways and mechanism for PSCs under working stressors. Then the strategies for improving long‐term durability with respect to fundamental materials, interface designs, and device encapsulation have been summarized. Meanwhile, the key results have been discussed to understand the limitation of assessing PSCs stability, and the potential applications in indoor photovoltaics and wearable electronics are demonstrated. Finally, promising proposals, encompassing material processing, film formation, interface strengthening, structure designing, and device encapsulation, are provided to improve the operational stability of PSCs and promote their commercialization. [ABSTRACT FROM AUTHOR]

Sweat sensors play a significant role in personalized healthcare by dynamically monitoring biochemical markers to detect individual physiological status. The specific response to the target biomolecules usually depends on natural oxidase, but it is susceptible to external interference. In this work, we report tryptophan- and histidine-treated copper metal-organic frameworks (Cu-MOFs). This amino-functionalized copper-organic framework shows highly selective activity for ascorbate oxidation and can serve as an efficient ascorbate oxidase-mimicking material in sensitive sweat sensors. Experiments and calculation results elucidate that the introduced tryptophan/histidine fundamentally regulates the adsorption behaviors of biomolecules, enabling ascorbate to be selectively captured from complex sweat and further efficiently electrooxidized. This work provides not only a paradigm for specifically sweat sensing but also a significant understanding of natural oxidase-inspired MOF nanoenzymes for sensing technologies and beyond. Sweat sensors are important in personalized healthcare using natural oxidase to target biomolecules but these reactions are susceptible to external interference. Here, the authors report tryptophan- and histidine-treated copper metal-organic frameworks which show highly selective activity for ascorbate oxidation and can serve as an efficient ascorbate oxidase-mimicking material in sensitive sweat sensors. [ABSTRACT FROM AUTHOR]

Summary: In this work, metal‐organic frameworks (MOFs), known as porous carbon, organic ligands, and crystalline materials have been reviewed as it consists of excellent properties, including high surface area, porosity, functional consistency, and uniform structure. The structural of MOFs, including secondary building units, open metal sites, pore sizes, functional materials, and development of MOF have been extensively studied as it helps to conduct electricity and promising good efficiency. To improve the performance in fuel cell applications, especially in catalytic activity such as oxygen reduction reaction and proton exchange membrane, the combination of MOF and other materials such as MOF/carbon material composites, MOF/metal nanoparticles (NPs), and MOF/biocomposites has been discussed in details, which can increase the potential and efficiency of catalysts. MOF‐derivatives, including MOF‐derived porous carbon, MOF‐derived NPs, MOF‐derived metal oxides, and MOF‐derived metal phosphide, has been provided in this review as it has its advantages; (a) increase the mass density of active sites, (b) increase intrinsic activity of active sites, (c) increase electrocatalyst conductivity (d), and accelerate electron transfer. Hence, it can produce materials with high thermal and chemical stability, embracing metal sites, and efficiency in active sites. These advantages have made the MOF a promising material to increase efficiency in fuel cell application and attract interest to further expand in other fields in the future. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) glasses have become a subject of interest as a distinct category of melt quenched glass, and have potential applications in areas such as ion transport and sensing. In this paper we show how MOF glasses can be combined with inorganic glasses in order to fabricate a new family of materials composed of both MOF and inorganic glass domains. We use an array of experimental techniques to propose the bonding between inorganic and MOF domains, and show that the composites produced are more mechanically pliant than the inorganic glass itself. Metal-organic frameworks constitute a family of glass formers that is distinct from those that are polymeric, metallic, or inorganic. Here the authors show that they can be combined with different inorganic aluminophosphate glasses to produce a composite with mechanical properties intermediate between the two end-members. [ABSTRACT FROM AUTHOR]