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This study addressed the formation of co‐crystals from Quercetin and Curcumin by mechanochemical treatment employing ball mill grinding. The binary system was initially studied using molecular complementarity and hydrogen bond propensity analysis structural tools available in Mercury software. This study was performed from CCDC reported structural data for Curcumin and Quercetin dihydrate used as starting reagents. Reaction conditions, such as Quercetin: Curcumin molar ratio, grinding time, and solvent‐assisted variables, were optimised to synthesise a new solid phase from the binary system. The synthesised product was characterised by differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and powder X‐ray diffraction techniques. Finally, to compare the anti‐oxidant capacities from the pure components, eutectic mixtures previously reported and the new crystalline phase was evaluated in vitro using the 1,1‐diphenyl‐2‐pycril‐hydrazylhydrate radical inhibition method. The co‐crystal phase and eutectic mixtures present higher anti‐oxidant activity with values around 5.0 mg/L compared to pure Quercetin (3,444 mg/L) and Curcumin (9,141 mg/L), using only half of the molecules. These results indicate Quercetin molecule is synergically active with the Curcumin molecule in the binary mixtures. [ABSTRACT FROM AUTHOR]

A new set of Ln‐MOF (lanthanide‐metal‐organic framework) thin films, known as Ln‐SURMOFs (surface‐supported MOFs), is fabricated with a layer‐by‐layer, in order to generate solid‐state white‐lighting devices. A three‐component approach is carried out for a rational combination of red, green, and blue (RGB) emitting Eu3+, Tb3+, and Gd3+ containing layers in order to achieve white‐light emission. The Ln‐SURMOFs are fully characterized by powder X‐ray diffraction, infrared reflection–absorption spectroscopy, scanning electron microscopy, and photoluminescence spectroscopy (excitation‐emission and chromaticity determination according to Commission International de l'Eclairage, CIE). The devices show CIE x,y coordinates of almost ideal white light (0.331, 0.329), as well as a correlated color temperature of 5570 K. Besides, the temperature dependent performance of the RGB‐SURMOFs is studied at room temperature and at 77 K. [ABSTRACT FROM AUTHOR]

Two lanthanide doped nanosystems Ca0.8Ln0.1Na0.1WO4 (Ln = Eu, Sm), denoted as Eu@CWO and Sm@CWO, were prepared by a "top-down" approach in three simple steps: activation, miniaturization by high-energy milling, and further calcination. The solids were thoroughly characterized by X-ray powder diffraction (XRPD) and Scanning-electron microscopy (SEM). Also, analyses of the structure of the compounds and the impact of milling on the crystallite shape and size were carried out through Rietveld refinements. Solid-state photoluminescence was studied in terms of excitation, emission, lifetimes (τobs) and europium-quantum yields. Finally, the Eu@CWO sample was employed as a potential water-stable chemical sensor towards toxic cations, showing a quenching effect in the presence of iron ions. [ABSTRACT FROM AUTHOR]