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Lead is one of the key metals of the all-inorganic lead halide perovskites. This work tailors novel architectures of lead's coordination sphere using a β-diketone (H-hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione) and a glyme (monoglyme, diglyme, triglyme, or tetraglyme) ligand. The coordination chemistry and thermal behaviour of these "Pb(hfa)2·glyme" adducts have been analysed through FT-IR spectroscopy, 1H and 13C NMR analyses, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Single-crystal X-ray diffraction studies provide evidence of the formation of a monomeric Pb(hfa)2·monoglyme structure. In order to validate the potentiality of these "Pb(hfa)2·glyme" precursors for the fabrication of Pb-based halide perovskites, a facile, one-step and low-temperature solution approach has been applied to prepare CsPbBr3 microcrystals with a process carried out in air under atmospheric pressure. Pure stoichiometric CsPbBr3 powders, obtained using Cs(hfa) and Br2 as cesium and bromide sources, respectively, show excellent stability under atmospheric conditions. Better results are obtained in terms of yield and stability from the diglyme and tetraglyme lead adducts. Field emission scanning electron microscopy (FE-SEM) indicates a good uniform morphology of cubic grains, while the structure and the 1 : 1 : 3 stoichiometry of Cs : Pb : Br are confirmed by X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX), respectively. Tauc plots derived from absorption spectroscopy point to optical energy band-gaps (Eg) in the 2.21–2.27 eV range, in agreement with literature data. The present research elucidates the potential of these novel "Pb(hfa)2·glyme" adducts as promising lead precursors for CsPbBr3 perovskite synthesis, paving the way for their implementation in various technological applications. [ABSTRACT FROM AUTHOR]

Significant work has recently focused on developing novel materials suitable for solar technologies with better conversion efficiencies, while maintaining low costs. BaF2 has been investigated as a fluoride host for doping with luminescent ions for energy conversion processes in photovoltaic cells. This work employed a metal–organic chemical vapor deposition technique to prepare nanostructured europium-doped BaF2 thin films on silicon and quartz substrates. Samples have been fabricated by varying the deposition temperature from 300 to 600 °C in order to examine how temperature affects the structure, morphology, and luminescence of Eu-doped BaF2 thin films. A multicomponent combination of fluorinated β-diketonate metal–organic precursors of barium and europium, Ba(hfa)2·tetraglyme and Eu(hfa)3·diglyme, in an appropriate molar ratio, is employed to fabricate BaF2 based thin films. These precursors serve as a single molten source by delivering all the elements required (Ba, Eu, and F) for forming the Eu-doped BaF2 phase due to the similar nature of the ligands. On silicon substrates, preliminary deposition tests have been carried out to confirm the purity, homogeneity, and appropriate stoichiometry of films. The obtained results pave the way for the production of BaF2 thin films doped with lanthanide ions, particularly interesting for their up-conversion (UC), down-conversion (DC), and down-shifting (DS) properties. [ABSTRACT FROM AUTHOR]

The development of highly active, low-cost, and robust electrocatalysts for the oxygen evolution reaction (OER) is a crucial endeavor for the clean and economically viable production of hydrogen via electrochemical water splitting. Herein, cuprous oxide (Cu 2 O) thin films are deposited on silver nanowire (AgNW) networks by atmospheric-pressure spatial atomic layer deposition (AP-SALD). AgNW@Cu 2 O nanocomposites supported on conductive copper electrodes exhibited superior OER activity as compared to bare copper substrate and bare AgNWs. Moreover, a relationship between Cu 2 O thickness and OER activity was established. Notably, the most effective catalyst (AgNW@50nm-thick Cu 2 O) demonstrated very high OER activity with a low overpotential of 409 mV to deliver a current density of 10 mA cm -2 ( η 10 ), a Tafel slope of 47 mV dec -1 , a turnover frequency (TOF) of 4.2 s -1 at 350 mV, and good durability in alkaline media (1 M KOH). This highlights the potential of AgNWs as a powerful platform for the formation of highly efficient copper oxide catalysts towards OER. This work provides a foundation for the development of nanostructured Cu-based electrocatalysts for future clean energy conversion and storage systems., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Lead is one of the key metals of the all-inorganic lead halide perovskites. This work tailors novel architectures of lead's coordination sphere using a β-diketone (H-hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione) and a glyme (monoglyme, diglyme, triglyme, or tetraglyme) ligand. The coordination chemistry and thermal behaviour of these "Pb(hfa) 2 ·glyme" adducts have been analysed through FT-IR spectroscopy, 1 H and 13 C NMR analyses, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Single-crystal X-ray diffraction studies provide evidence of the formation of a monomeric Pb(hfa) 2 ·monoglyme structure. In order to validate the potentiality of these "Pb(hfa) 2 ·glyme" precursors for the fabrication of Pb-based halide perovskites, a facile, one-step and low-temperature solution approach has been applied to prepare CsPbBr 3 microcrystals with a process carried out in air under atmospheric pressure. Pure stoichiometric CsPbBr 3 powders, obtained using Cs(hfa) and Br 2 as cesium and bromide sources, respectively, show excellent stability under atmospheric conditions. Better results are obtained in terms of yield and stability from the diglyme and tetraglyme lead adducts. Field emission scanning electron microscopy (FE-SEM) indicates a good uniform morphology of cubic grains, while the structure and the 1 : 1 : 3 stoichiometry of Cs : Pb : Br are confirmed by X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX), respectively. Tauc plots derived from absorption spectroscopy point to optical energy band-gaps ( E g ) in the 2.21-2.27 eV range, in agreement with literature data. The present research elucidates the potential of these novel "Pb(hfa) 2 ·glyme" adducts as promising lead precursors for CsPbBr 3 perovskite synthesis, paving the way for their implementation in various technological applications.