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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]

Coordination networks (CNs) with tailorable multi‐metallic composition were designed and then used as sacrificial materials to obtain promising materials with Up‐conversion (UC) properties. The metal‐organic precursors led to solid solutions of Rare‐Earth Oxides (REO)Y2O3:Yb3+/Er3+ or Y2O3:Yb3+/Er3+/Gd3 through a calcination process. In order to obtain luminescent UC platforms, spin‐coating technique was implemented to deposit these materials onto glass supports. The synthesized solids and the resulting films were characterized by Scanning Electron Microscopy – Energy Dispersive Spectroscopy (SEM‐EDS), infrared spectroscopy, powder (PXRD), and grazing incidence (GIXRD) X‐ray diffraction techniques. Moreover, the photophysical properties of bulk and deposited Y2O3:Ln3+ doped oxides were evaluated after being irradiated with NIR wavelength (980 nm) laser to excite the Yb3+ sensitizer ion. Besides, decay emission profiles from each sample were also obtained and lifetime (τobs) values were calculated. These results open up the implementation of REO thin films obtained through CN calcination for promising applications such as solar cells and sensor devices. [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]