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Advances in energy‐efficient lighting and display technologies demand innovative materials with tailored broad‐spectrum emission properties. Hybrid aggregation‐induced emission metal‐organic frameworks (AIE‐MOFs) offer a promising avenue, combining unique characteristics of organic and inorganic components to yield enhanced luminescence efficiency and robust material stability. The study introduces a spectrum of D (donor)‐A (acceptor) type AIE‐active ligands into MOFs, enabling tunable emission across the visible spectrum, thus underscoring the versatility of these hybridized MOF materials. The emission properties of AIE‐MOFs are further harnessed by integrating them into polymer matrices, resulting in high‐performance electrospun fibers with tunable emission. A significant achievement involves the fabrication of Janus‐type white light‐emitting AIE‐MOF fiber composites via side‐by‐side electrospinning, accomplishing a high quantum yield of 58%, which doubled the performance of homogeneous fibers. Complementing the experimental findings, micro‐Raman and nano‐Fourier transform infrared spectroscopy are employed as local spectroscopic probes, affording a deeper understanding of the material properties and the mechanisms contributing to enhance light emission. In the understanding, this study presents an unconventional implementation of hybrid AIE‐MOFs in Janus‐type structures for white light emission. It significantly improves the efficiency of white light sources in optoelectronics, charting a promising direction for future research in the emergent AIE‐MOF field. [ABSTRACT FROM AUTHOR]

Despite exhaled human breath having enabled noninvasive diabetes diagnosis, selective acetone vapor detection by fluorescence approach in the diabetic range (1.8–3.5 ppm) remains a long‐standing challenge. A set of water‐resistant luminescent metal‐organic framework (MOF)‐based composites have been reported for detecting acetone vapor in the diabetic range with a limit of detection of 200 ppb. The luminescent materials possess the ability to selectively detect acetone vapor from a mixture comprising nitrogen, oxygen, carbon dioxide, water vapor, and alcohol vapor, which are prevalent in exhaled breath. It is noteworthy that this is the first luminescent MOF material capable of selectively detecting acetone vapor in the diabetic range via a turn‐on mechanism. The material can be reused within a matter of minutes under ambient conditions. Industrially pertinent electrospun luminescent fibers are likewise fabricated alongside various luminescent films for selective detection of ultratrace quantities of acetone vapor present in the air. Ab initio theoretical calculations combined with in situ synchrotron‐based dosing studies uncovered the material's remarkable hypersensitivity toward acetone vapor. Finally, a freshly designed prototype fluorescence‐based portable optical sensor is utilized as a proof‐of‐concept for the rapid detection of acetone vapor within the diabetic range. [ABSTRACT FROM AUTHOR]

Metal–organic polyhedra (MOPs) are discrete, metal–organic molecular entities composed of edge‐sharing molecular polygons or connected molecular vertices. Unlike the infinite metal–organic coordination networks popularized by metal–organic frameworks (MOFs), spherical MOPs, also known as nanocages, nanospheres, nanocapsules, or nanoballs, are obtained through the self‐organization of metal–carboxylate or metal–pyridine/pyrimidine links to afford cage‐like nanoarchitectures. MOPs offer much promise as porous materials owing to their well‐defined structures and solution processability. However, these advantages become moot if their poor aqueous stability and/or guest‐removal‐induced aggregation handicaps remain unaddressed. The concise premise of this contribution limits our discussion to the design principles in action behind recent developments in stable carboxylate MOPs. To highlight the structure–property relationships between the structural and compositional features of these metal carboxylate polyhedra, related scientific challenges and state‐of‐the‐art research directions for further exploration are presented in brief. [ABSTRACT FROM AUTHOR]

Front Cover: Stabilizing Metal-Organic Polyhedra (MOP): Issues and Strategies (Chem. B Cage compounds b : Metal-organic polyhedra (MOPs) are discrete, metal-organic molecular entities composed of edge-sharing molecular polygons or connected molecular vertices that offer much promise as porous materials owing to their well-defined structures and solution processability. Cage compounds, hydrolytic stability, hydrophobicity, metal-organic polyhedra, self-assembly. [Extracted from the article]

Metal-organic polyhedra (MOP) are a promising class of crystalline porous materials with multifarious potential applications. Although MOPs and metal-organic frameworks (MOFs) have similar potential in terms of their intrinsic porosities and physicochemical properties, the exploitation of carboxylate MOPs is still rudimentary because of the lack of systematic development addressing their chemical stability. Herein we describe the fabrication of chemically robust carboxylate MOPs via outer-surface functionalization as an a priori methodology, to stabilize those MOPs system where metal-ligand bond is not so strong. Fine-tuning of hydrophobic shielding is key to attaining chemical inertness with retention of the framework integrity over a wide range of pH values, in strong acidic conditions, and in oxidizing and reducing media. These results are further corroborated by molecular modelling studies. Owing to the unprecedented transition from instability to a chemically ultra-stable regime using a rapid ambient-temperature gram-scale synthesis (within seconds), a prototype strategy towards chemically stable MOPs is reported., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)