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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]

Among semiconductor metal oxides, that are an important class of sensing materials, titanium dioxide (TiO2) thin films are widely employed as sensors because of their high chemical and mechanical stability in harsh environments, non-toxicity, eco-compatibility, and photocatalytic properties. TiO2-based chemical oxygen demand (COD) sensors exploit the photocatalytic properties of TiO2 in inducing the oxidation of organic compounds to CO2. In this work, we discuss nanostructured TiO2 thin films grown via low-pressure metal organic chemical vapor deposition (MOCVD) on metallic AISI 316 mesh. To increase the surface sensing area, different inorganic acid-based chemical etching protocols have been developed, determining the optimal experimental conditions for adequate substrate roughness. Both chemically etched pristine meshes and the MOCVD-coated ones have been studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) microanalysis, and X-ray photoelectron spectroscopy (XPS). We demonstrate that etching by HCl/H2SO4 at 55 °C provides the most suitable surface morphology. To investigate the behavior of the developed high surface area TiO2 thin films as COD sensors, photocatalytic degradation of functional model pollutants based on ISO 10678:2010 has been tested, showing for the best performing acid-etched mesh coated with polycrystalline TiO2 an increase of 60% in activity, and degrading 66 µmol of MB per square meter per hour. [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 [...]

We report the deposition of monolayers and multilayers of {Cr10(OMe)20(O2CCMe3)10} wheels, hereafter {Cr10}, onto Au(111) and Cu(111) single‐crystal substrates, and their characterization combining scanning tunneling microscopy, X‐ray photoelectron spectroscopy, X‐ray absorption spectroscopy, X‐ray natural linear dichroism, and X‐ray magnetic circular dichroism (XMCD). {Cr10} in bulk shows axial magnetic anisotropy and a cluster total spin S = 9 ground state, stemming from an interaction scheme of two semi‐crowns containing four Cr3+ ions interacting ferromagnetically, separated by two Cr3+ antiferromagnetically coupled. The one‐monolayer (1ML) samples of {Cr10} sublimated on Ag(111) and Cu(111) show slightly different applied magnetic field dependence of XMCD signal. The field‐dependence of the magnetization evolves from a lower curve for the 1ML {Cr10} samples to a curve resembling the bulk one as the number of layers is increased, as shown in a 14ML sample. Monte Carlo simulations allow rationalizing the magnetization curves of the 1ML samples in terms of a reduction of the cluster ground‐state total spin, S = 3 or S = 6, as a consequence of variations in the intra‐wheel coupling interactions induced by the on‐surface deposition. The sensitivity of the magnetic configuration of {Cr10} to minor distortions of the intramolecular conformation might be exploited to control magnetism by external stimuli for applications. [ABSTRACT FROM AUTHOR]

SPIDER is the 100 keV full-size Negative Ion Source prototype of the ITER Neutral Beam Injector, operating at Consorzio RFX in Padova, Italy. The largest Negative Ion Source in the world, SPIDER generates an RF driven plasma from which Deuterium or Hydrogen negative ions are produced and extracted. At the end of 2021, a scheduled long-term shutdown started to introduce major modifications and improvements aiming to solve issues and drawbacks identified during the first three years of SPIDER operations. The first action of the shutdown period was the disassembly and characterization of the SPIDER beam source after removal from the vacuum vessel and its placement inside the clean room. Each component was carefully assessed and catalogued, following a documented procedure. Some source components, i.e., the Plasma Grid, Extraction Grid and Bias Plate, revealed the presence of different and non-uniform red, white and green coatings that might be correlated to back-streaming positive ions impinging on grid surfaces, electrical discharges and caesium evaporation. Thus, several analyses have been carried out to understand the nature of such coatings, with the study still ongoing. The evidence of caesium evaporation and deposition on molybdenum-coated SPIDER components, such as the formation of oxides and hydroxides, is demonstrated through surface characterization analyses with the use of the Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). [ABSTRACT FROM AUTHOR]