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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 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]

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]

Abstract: Reaction between EuCl3 and the ligand 1,3-di(thien-2-yl)propane-1,3-dione (L) leads to luminescent coordination compounds [Eu[L.sub.3][(EtOH).sub.2]](1), [Eu[L.sub.2][(i-PrOH).sub.4]]Cl (2) and [Eu[L.sub.3]([(i-PrOH).sub.2]](3), isolated as single crystals in high yield (70%-95%). The Eu/[beta]-diketonate ratio [...]

The similar reactivity of lanthanides generally leads to statistically populated polynuclear complexes, making the rational design of ordered hetero‐lanthanide compounds extremely challenging. Here we report on the site selectivity in hetero‐lanthanide tetranuclear complexes afforded by the relatively simple ditopic pyterpyNO ligand (4'‐(4‐pyridil)‐2,2':6',2"‐terpyridine N‐oxide). The sequential room temperature reaction of RE2(tta)6(pyterpyNO)2 (where RE=Y, (1); Eu, (2), Dy, (3) Htta=2‐thenoyltrifluoroacetone) with La(tta)3dme (dme=dimethoxyethane) yielded Y2La2(tta)12(pyterpyNO)2 (4), Dy2La2(tta)12(pyterpyNO)2 (5) and Eu2La2(tta)12(pyterpyNO)2 (6). Single crystals X‐ray diffraction studies showed that 4, 5 and 6 are isostructural, featuring a tetranuclear structure with two different metal coordination sites with coordination numbers 8 (CN8) and 9 (CN9). The two smaller cations are mainly bridged by the O‐donor atoms of the NO groups of two pyterpyNO ligands (CN8), while the larger lanthanum centres are bound by a terpyridine unit (CN9). Size selectivity has been studied with structural and magnetic studies in the solid state and through 19F NMR and photoluminescence studies in solution, showing a direct dependence on the difference of ionic radii of the ions and yielding a 91 % selectivity for 4. Furthermore, 19F NMR, X‐ray and PL studies pointed out that the nature of the product is independent from the synthetic route for compound Eu2Y2(tta)12(pyterpyNO)2 (7), keeping the ion selectivity also for a self‐assembly reaction. Unexpectedly, these studies have evidenced that selectivity is not exclusively governed by electrostatic interactions related to size dimensions. [ABSTRACT FROM AUTHOR]

Oxidized carbon nanohorn water based nanofluids are attracting more and more attention for solar harvesting applications because of their peculiar features: stable suspension without any surfactant, higher solar absorbance values as compared to the base fluid, etc. However, these nanofluids are still matter of research because not all their properties have been comprehensively studied yet. This paper is focused on the wettability properties of the carbon nanohorn water based nanofluids on different metal surfaces. The static contact angle was measured for ten nanofluids with concentrations ranging from 0.002%wt to 0.1% wt, five of those used non-oxidized carbon nanohorns while the other five used oxidized carbon nanohorns. Moreover, this work investigates a novel use of the oxidized carbon nanohorn nanofluids to deposit an ultra-thin layer via pool boiling. The realized coating was proved to be stable and found to slightly affect the wettability of the nanofluids. Finally, the solar reflectance of the coated aluminum sample was measured and found to be from 2 to 10 times lower as compared to a reference aluminum surface. [ABSTRACT FROM AUTHOR]