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The coordinating properties of the bis(1,4‐dimethyl‐1,2,4‐triazol‐5‐ylidene) ligand (abbreviated as bitz) towards silver(I) and gold(I) centres have been explored. The bitz behaves as bridging ligand giving both dinuclear [M2(bitz)2](PF6)2 and trinuclear [M3(bitz)3](PF6)3 species, whose formation has been supported by X‐ray diffraction analysis, NMR spectroscopy and mass spectrometry evidences. The dinuclear and trinuclear gold(I) complexes present very similar luminescence properties, emitting in the blue region, at ~450 nm, when excited at 350 nm. Selected experimental aspects dealing with the synthesis of the dinuclear and trinuclear species, as well as with the absorption properties of the gold(I) complexes, have been investigated also through relativistic DFT calculations. [ABSTRACT FROM AUTHOR]

The integration of photovoltaic (PV) devices into the built environment has become a key factor for the development of energy efficient buildings. Luminescent solar concentrators (LSCs) are well suited for this application, as they could be installed over architectural elements inaccessible to conventional PVs. In the present work, we report the synthesis of super-bright [Eu2L4]2− cages bearing bis-β-diketonate ligands and their subsequent embedding in polymethylmethacrylate (PMMA) by casting of 5 × 5 × 0.27 cm3 planar LSCs. With a measured average visible transmittance (AVT) of 92%, the proposed LSCs possess excellent transparency and aesthetic quality fit for glass destined for neutral colour applications. Moreover, the obtained materials absorb from 60% to 90% of solar UV radiation, exposure to which is harmful for human health and responsible for fading of building interiors. The performance of devices attained by edge-coupling LSC slabs with monocrystalline silicon solar cells matches that of classic Eu3+-based concentrators. Nonetheless, the employment of super-bright [Eu2L4]2− luminophores allows the reduction of the Eu3+ ion content of our devices down to 0.01% wt. This denotes a most efficient use of a valuable material like europium in the developed LSC-PVs, as Eu3+ weight contents reported in relevant literature were one to two orders of magnitude higher. [ABSTRACT FROM AUTHOR]

The "on‐demand" capture and utilization of CO2 is effectively realized with a readily accessible dual function organic composite. The covalent and controlled derivatization of graphene oxide (GO) surface with naturally occurring arginine led to a "smart" material capable of capturing (chemisorption) CO2 from high‐purity flue‐gas as well as low‐concentration streams (i. e. direct air capture) and concomitant chemical activation toward the incorporation into cyclic carbonates. The overall integrated CO2 capture and conversion (ICCC) strategy has been fully elucidated mechanistically via dedicated computational, spectroscopic and thermal analyses. [ABSTRACT FROM AUTHOR]

A novel copper iodide hybrid compound, (DABCO-H)CuKI3, featuring a perovskite structure is here reported. Characterization techniques, including single crystal X-ray diffraction, X-ray photoelectron spectroscopy (XPS), and photoluminescence studies, elucidate the structural and luminescent properties. The compound exhibits blue phosphorescence, attributed to mixed metal-to-ligand and halide-to-ligand charge transfer transitions, as supported by density functional theory (DFT) calculations and XPS valence band analysis. Furthermore, (DABCO-H)CuKI3 displays a remarkable adsorption capacity towards methylene blue dye. Kinetic modelling reveals that both film and intra-particle diffusion processes contribute to the adsorption rate. [ABSTRACT FROM AUTHOR]

This work reports single-crystal X-ray diffraction (XRD), Scanning Tunneling Microscopy (STM), and quantum mechanics calculations of the 310-helical peptide Z-(Aib)2-L-Dap(Boc)-Aib-NHiPr (Aib, α-aminoisobutyric acid; Dap, 2,3-diaminopropionic acid; Z, benzyloxycarbonyl; Boc, t-butoxycarbonyl). The peptide forms a double-helical superstructure, studied by XRD and STM. Such architecture is rare in short peptides. Here, we show, by combining XRD, STM that this intriguing conformational feature is not driven by crystal packing; rather, it is an intrinsic property of this peptide. Indeed, the double helix is clearly detected also by STM, where crystal packing cannot be invoked. XRD reveals that intermolecular H-bonds stabilize two left-handed supra-helices (tertiary structure) that develop around a 6-fold screw axis. Then, two supra-helices are intertwined in a quaternary structure as a left-handed, double supra-helix, where C-H⋯π interactions play a crucial role. STM images show the formation of long, isolated "necklaces" (> 110 nm). They are of left and right helical handedness. Their size agrees with the XRD finding. DFT calculations allowed us to weigh the contribution of the different intermolecular interactions in the two single supra-helices and the supramolecular double-helix. Interestingly, we were able to conclude that the contribution of the C-H⋯π interactions to the binding energies is close to 50%., (© 2024 Wiley‐VCH GmbH.)

The "on-demand" capture and utilization of CO 2 is effectively realized with a readily accessible dual function organic composite. The covalent and controlled derivatization of graphene oxide (GO) surface with naturally occurring arginine led to a "smart" material capable of capturing (chemisorption) CO 2 from high-purity flue-gas as well as low-concentration streams (i. e. direct air capture) and concomitant chemical activation toward the incorporation into cyclic carbonates. The overall integrated CO 2 capture and conversion (ICCC) strategy has been fully elucidated mechanistically via dedicated computational, spectroscopic and thermal analyses., (© 2024 Wiley-VCH GmbH.)