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The synthesis and characterization of a family of copper(i) complexes bearing a bridged bis-pyridyl ancillary ligand is reported, highlighting how the bridge nature impacts the photo- and electro-luminescent behaviours within the family. In particular, the phosphonium bridge led to copper(i) complexes featuring good electrochemical stability and high ionic conductivity, as well as a stark blue-to-orange luminescence shift compared to the others. This resulted in high performance light-emitting electrochemical cells reaching stabilities of 10 mJ at ca. 40 cd m(-2) that are one order of magnitude higher than those of the other complexes. Overall, this work sheds light onto the crucial role of the bridge nature of the bis-pyridyl ancillary ligand on the photophysical features, film forming and, in turn, on the final device performances., Funding Agencies|Ministere de la Recherche et des Nouvelles Technologies; CNRS (Centre National de la Recherche Scientifique)Centre National de la Recherche Scientifique (CNRS); LABEX SynOrg [ANR-11-LABX-0029]; Region NormandieRegion Normandie; Normandie University; European UnionEuropean Commission [863170]; ERC-Co InOutBioLight [816856]; MSCA-ITN STiBNite [956923]; Spanish Ministerio de Ciencia, Innovacion y Universidades [RTI2018-097508-B-I00]; European UnionEuropean Commission; Comunidad de MadridComunidad de Madrid [S2018/NMT-4511]; "Severo Ochoa" Programme for Centres of Excellence in RD (MINECO) [SEV-2016-0686]; SeRC (Swedish e-Science Research Center)

Synthesis, processing, and characterization are reported for a series of tetracyanoplatinate Magnus' salt (TCN-MS) derivatives-soluble derivatives of the generally intractable Magnus' green salt-that feature the general structure [Pt(NH2R)(4)] [Pt(CN)(4)] where R is a branched alkyl group or a w-phenylalkyl group. In solutions, these coordination compounds generally dissolve on the level of individual ion pairs as shown by X-ray diffraction analysis. To enable the formation of quasi-one-dimensional linear stacks of Pt(II) atoms in thin films, the matrix-assisted assembly is employed, whereby the compounds are codissolved with poly(ethylene oxide) (PEO), followed by film casting, thermally activated assembly, and eventual removal of PEO. Remarkably, assembled TCN-MS inorganic polymers exhibit bright blue-green photoluminescence. A detailed investigation of the assembly process and simultaneously modified solid-state optical properties is performed using a range of microscopy, optical and vibrational spectroscopy, and thermal analysis techniques. Given their unusual combination of optical properties, namely, transparency in the visible region, high photoluminescence quantum efficiencies (up to 13% in first-demonstration samples), and large Stokes shifts (up to 1 eV), TCN-MS derivatives are proposed as a promising class of light-emitting materials for emerging applications in molecular optoelectronics, the potential and challenges of which are discussed.

We report on a combinatorial optimization procedure applied to heterojunction small molecule organic solar cells made of evaporated copper phthalocyanine (CuPc) and 3,4,9,10-perylenetetracarboxylic bisbenzimidazole (PTCBI). Our strategy consists of depositing both light harvesting compounds as orthogonally arranged wedge-shaped layers to then determine the optimum thicknesses which yield the highest photoconversion efficiency. The device performance is locally assessed by means of light-beam induced current images. A quantitative model of co-locally measured Raman images allows determining the corresponding local thicknesses of the active layers. The spatial correlation of both datasets (i.e. local photocurrent density and active layer film thicknesses) enables the rapid optimization of the photovoltaic system studied employing a single functional device, reducing in approximately 20 times the use of resources and time.

Amongst the different optoelectronic applications of conjugated polymers, waveguide amplifiers and optically pumped lasers are those requiring larger photochemical stability, owing to the large irradiation conditions under operation. In this context, suitable waveguide optimization enabling the reduction of amplified spontaneous emission (ASE) threshold values appears as important as synthetic chemistry protocols to promote polymer robustness against photo-oxidation. In this work, we develop rib waveguides with different geometries based on four different fluorene-based compounds and assess the influence of rib confinement on ASE properties. We observe ASE threshold values as low as 8.9 × 10-4 mJ cm-2, being among the lowest threshold values reported so far on blue emitting polymer/oligomer waveguides. We demonstrate that the enhanced ASE efficiency on some of these rib waveguides leads to a fivefold increase in operation lifetime respect to spin-coated slab waveguides, thus confirming the impact of waveguide geometry on ASE operation stability.

Amplified spontaneous emission under millisecond pulsed excitation on a rotaxane-insulated conjugated polymer is reported. Pump-probe spectroscopy confirms the absence of polaron-pair absorption in the gain spectral region as the main factor contributing to quasi-steady-state amplified spontaneous emission. The low polaron-pair yield in this compound is the likely result of effective backbone encapsulation provided by the threading ring. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

El fotodetector comprende una capa activa continua en la que al incidir la luz genera una señal proporcional a la posición en la que incide dicha luz; se caracteriza porque la capa activa comprende un primer y un segundo semiconductor orgánico distribuidos según un gradiente longitudinal correspondiente a un gradiente de concentración relativa, un gradiente d estructura o ambos.La invención también se refiere al procedimiento de obtención del fotodetector y al procedimiento de medida de la respuesta del fotodetector.Permite obtener un sensor continuo de mayores dimensiones que los previstos en el estado de la técnica, aumentando su radio de acción sin alterar su sensibilidad.

[EN] The invention relates to a photodetector comprising a continuous active layer in which, in response to incident light, a signal is generated that is proportional to the incident position of the light. The invention is characterised in that the active layer comprises frrst (1) and second (2) organic semiconductors distributed along a longitudinal gradient corresponding to a relative concentration gradient, a structure gradient or both. The invention also relates to the method for obtaining the photodetector and to the method for measuring the response from the photodetector. The invention can be used to obtain a continuous sensor of larger dimensions than those known in the prior art, thereby increasing the operating range without altering the sensitivity thereof., [ES] El fotodetector comprende una capa activa continua en la que al incidir luz genera una señal proporcional a la posición en la que incide dicha luz; se caracteriza porque la capa activa comprende un primer (1) y un segundo semiconductor orgánico (2) distribuidos según un gradiente longitudinal correspondiente a un gradiente de concentración relativa, un gradiente de estructura o ambos. La invención también se refiere al procedimiento de obtención del fotodetector y al procedimiento de medida de la respuesta del fotodetector. Permite obtener un sensor continuo de mayores dimensiones que los previstos en el estado de la técnica, aumentando su radio de acción sin alterar su sensibilidad.