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In this work we report a strategy for generating porosity in hybrid metal halide materials using molecular cages that serve as both structure‐directing agents and counter‐cations. Reaction of the [2.2.2] cryptand (DHS) linker with PbII in acidic media gave rise to the first porous and water‐stable 2D metal halide semiconductor (DHS)2Pb5Br14. The corresponding material is stable in water for a year, while gas and vapor‐sorption studies revealed that it can selectively and reversibly adsorb H2O and D2O at room temperature (RT). Solid‐state NMR measurements and DFT calculations verified the incorporation of H2O and D2O in the organic linker cavities and shed light on their molecular configuration. In addition to porosity, the material exhibits broad light emission centered at 617 nm with a full width at half‐maximum (FWHM) of 284 nm (0.96 eV). The recorded water stability is unparalleled for hybrid metal halide and perovskite materials, while the generation of porosity opens new pathways towards unexplored applications (e.g. solid‐state batteries) for this class of hybrid semiconductors. [ABSTRACT FROM AUTHOR]

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In their Research Article (e202218429), Ioannis Spanopoulos and co-workers report a strategy for generating porosity in hybrid metal halide semiconductors by using molecular cages as both structure-directing agents and counter-cations. Keywords: Broad Light Emission; Gas Separation; Microporous Materials; Semiconductors; Water Stability EN Broad Light Emission Gas Separation Microporous Materials Semiconductors Water Stability 1 1 1 03/09/23 20230313 NES 230313 B Porous and water-stable b hybrid semiconductors as multifunctional materials display traits that are essential for demanding commercial applications. Inside Cover: Porous and Water Stable 2D Hybrid Metal Halide with Broad Light Emission and Selective H2O Vapor Sorption (Angew. [Extracted from the article]

One of the primary methods for band gap tuning in metal halide perovskites has been halide (I/Br) mixing. Despite widespread usage of this type of chemical substitution in perovskite photovoltaics, there is still little understanding of the structural impacts of halide alloying, with the assumption being the formation of ideal solid solutions. The FASnI 3- x Br x ( x = 0-3) family of compounds provides the first example where the assumption breaks down, as the composition space is broken into two unique regimes ( x = 0-2.9; x = 2.9-3) based on their average structure with the former having a 3D and the latter having an extended 3D (pseudo 0D) structure. Pair distribution function (PDF) analyses further suggest a dynamic 5 s 2 lone pair expression resulting in increasing levels of off-centering of the central Sn as the Br concentration is increased. These antiferroelectric distortions indicate that even the x = 0-2.9 phase space behaves as a nonideal solid-solution on a more local scale. Solid-state NMR confirms the difference in local structure yielding greater insight into the chemical nature and local distributions of the FA + cation. In contrast to the FAPbI 3- x Br x series, a drastic photoluminescence (PL) quenching is observed with x ≥ 1.9 compounds having no observable PL. Our detailed studies attribute this quenching to structural transitions induced by the distortions of the [SnBr 6 ] octahedra in response to stereochemically expressed lone pairs of electrons. This is confirmed through density functional theory, having a direct impact on the electronic structure.

Hybrid metal halide semiconductors are a unique family of materials with immense potential for numerous applications. For this to materialize, environmental stability and toxicity deficiencies must be simultaneously addressed. We report here a porous, visible light semiconductor, namely, (DHS)Bi 2 I 8 (DHS = [2.2.2] cryptand), which consists of nontoxic, earth-abundant elements, and is water-stable for more than a year. Gas- and vapor-sorption studies revealed that it can selectively and reversibly adsorb H 2 O and D 2 O at room temperature (RT) while remaining impervious to N 2 and CO 2 . Solid-state NMR measurements and density functional theory (DFT) calculations verified the incorporation of H 2 O and D 2 O in the molecular cages, validating the porous nature. In addition to porosity, the material exhibits broad band-edge light emission centered at 600 nm with a full width at half-maximum (fwhm) of 99 nm, which is maintained after 6 months of immersion in H 2 O. Moreover, (DHS)Bi 2 I 8 exhibits bacteriocidal action against three Gram-positive and three Gram-negative bacteria, including antibiotic-resistant strains. This performance, coupled with the recorded water stability and porous nature, renders it suitable for a plethora of applications, from solid-state batteries to water purification and disinfection.

In this work we report a strategy for generating porosity in hybrid metal halide materials using molecular cages that serve as both structure-directing agents and counter-cations. Reaction of the [2.2.2] cryptand (DHS) linker with Pb II in acidic media gave rise to the first porous and water-stable 2D metal halide semiconductor (DHS) 2 Pb 5 Br 14 . The corresponding material is stable in water for a year, while gas and vapor-sorption studies revealed that it can selectively and reversibly adsorb H 2 O and D 2 O at room temperature (RT). Solid-state NMR measurements and DFT calculations verified the incorporation of H 2 O and D 2 O in the organic linker cavities and shed light on their molecular configuration. In addition to porosity, the material exhibits broad light emission centered at 617 nm with a full width at half-maximum (FWHM) of 284 nm (0.96 eV). The recorded water stability is unparalleled for hybrid metal halide and perovskite materials, while the generation of porosity opens new pathways towards unexplored applications (e.g. solid-state batteries) for this class of hybrid semiconductors., (© 2023 Wiley-VCH GmbH.)

Crystals of the title compound, C 17 H 15 N 2 + ·BF 4 - , were unexpectedly grown from crystallization attempts of [Pt(4,4'-bpy) 4 ](BF 4 ) 2 [Smith et al. (2019 ▸). Comments Inorg. Chem. 39 , 188-215] using toluene and aceto-nitrile. The tetra-fluoro-borate anion and the central pyridinium ring of the cation are disordered, with atomic site occupancies close to ½. The tolyl group of the cation has a 75.31 (11)° twist relative to the unsubstituted pyridyl group. This rotation allows for a centrosymmetric dimer of cations with weak hydrogen bonding between the pyridyl nitro-gen atom and a methyl H atom on the neighbouring cation., (© Welton et al. 2022.)