We report on the generation of bright white luminescence through solid-state illumination of remote phosphors based on novel cycloplatinated N-heterocyclic carbene (NHC) compounds. Following a stepwise protocol we got the new NHC compound [{Pt(μ-Cl)(C(∧)C*)}2] (4) (HC(∧)C*-κC* = 1-(4-(ethoxycarbonyl)phenyl)-3-methyl-1H-imidazol-2-ylidene), which was used together with the related ones 4a (HC(∧)C*-κC*= 1-(4-cyanophenyl)-3-methyl-1H-imidazol-2-ylidene) and 4b (HC(∧)C*-κC*= 3-methyl-1-(naphthalen-2-yl)-1H-imidazol-2-ylidene) as starting materials for the synthesis of the new ionic derivatives [Pt(R-C(∧)C*) (CNR')2]PF6 (R = -COOEt, R' = t-Bu (5), Xyl (6); R = -CN, R' = t-Bu (7), Xyl (8); R(∧)C = Naph, R' = t-Bu (9), Xyl (10)). The X-ray structures of 6 and 8-10 have been determined. The photophysical properties of these cationic compounds have been studied and supported by the time-dependent-density functional theory (TD-DFT) calculations. The compounds 5, 8, and 9 have been revealed as the most efficient emitters in the solid state with quantum yields of 41%, 21%, and 40%, respectively. White-light remote-phosphors have been prepared just by stacking different combinations of these compounds and [Pt(bzq) (CN) (CN(t)Bu)] (R1) as blue (5, 8), yellow (9), and red (R1) components onto the same substrate. The CCT (correlated color temperature) and the CRI (color rendering index) of the emitted white-light have been tuned by accurately controlling the individual contributions.

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The use of cermets as fuel electrodes for solid oxide electrolysis cells requires permanent circulation of reducing gas, e.g. H2 or CO, so called safe gas, in order to avoid oxidation of the metallic phase. Replacing metallic based electrodes by pure oxides is therefore proposed as an advantage for the industrial application of solid oxide electrolyzers. In this work, full-ceramic symmetrical solid oxide electrolysis cells have been investigated for steam/CO2 co-electrolysis. Electrolyte supported cells with La(0.75)Sr(0.25)Cr(0.5)Mn(0.5)O3-δ reversible electrodes have been fabricated and tested in co-electrolysis mode using different fuel compositions, from pure H2O to pure CO2, at temperatures between 850-900 °C. Electrochemical impedance spectroscopy and galvanostatic measurements have been carried out for the mechanistic understanding of the symmetrical cell performance. The content of H2 and CO in the product gas has been measured by in-line gas micro-chromatography. The effect of employing H2 as a safe gas has also been investigated. Maximum density currents of 750 mA cm(-2) and 620 mA cm(-2) have been applied at 1.7 V for pure H2O and for H2O : CO2 ratios of 1 : 1, respectively. Remarkable results were obtained for hydrogen-free fuel compositions, which confirmed the interest of using ceramic oxides as a fuel electrode candidate to reduce or completely avoid the use of safe gas in operation minimizing the contribution of the reverse water shift reaction (RWSR) in the process. H2 : CO ratios close to two were obtained for hydrogen-free tests fulfilling the basic requirements for synthetic fuel production. An important increase in the operation voltage was detected under continuous operation leading to a dramatic failure by delaminating of the oxygen electrode.

Nanocomposites consisting of a dielectric matrix, such as TiO2, with embedded noble metal nanoparticles (NPs) possess specific optical properties due to the surface plasmon resonance (SPR) effect, interesting for several applications. The aim of this work is to demonstrate that these properties are sensitive to the nanostructure of magnetron-sputtered TiO2/Au thin films, which can be tuned by annealing. We study the role of the shape and size distribution of the NPs, as well as the influence of the crystallinity and phase composition of the host matrix on the optical response of the films. All these characteristics can be modified by vacuum annealing treatments of the deposited films. A theoretical interpretation and modeling of the experimental results obtained is presented. The model involves a modified Maxwell-Garnett approach for the effective dielectric function of the composite (describing the SPR effect) and the transfer matrix formalism for multilayer optics. Input data are based on the experimental information obtained from the detailed structural characterization of the films. It is shown that the annealing treatments can be used for controlling the optical properties of the composite films, making them attractive for decorative coatings.

Improving of SOCs performance by 3D printing are proved, increasing the active area by high-aspect ratio structuration of their components.