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+7 9117294724 1. AbstractThis work proposes new chemical and mechanical materials and techniques for III-V semiconductor NW/silicone membrane formation and optoelectronic device fabrication. Molecular beam epitaxy (MBE)-synthesized n-, p-and i-GaP NWs were encapsulated by introduced G-coating method into synthesized polydimethylsiloxane-graft-polystyrene and released from the Si growth substrate. The fabricated membranes were contacted with different materials including single-walled carbon nanotubes or ferrocenyl-containing polymethylhydrosiloxane with and without multi-walled carbon nanotubes doping. The electrical connection of the fabricated membranes was verified by electron beam induced current (EBIC) spectroscopy. The developed methods and materials can be applied for fabrication of high quality flexible inorganic optoelectronic devices. IntroductionThe appealing properties of organic light emitting diodes (OLEDs), i. e. relatively easy and inexpensive fabrication, and efficient electroluminescence (EL) allowed the OLED-based industry to conquer a significant market share. For instance, modern smartphones are mostly produced with the OLED displays [weblink1, weblink2]. However, organic materials are far behind the inorganic materials in terms of stability and external quantum efficiency (EQE) of EL

Cobalt(II)-pyridinedicarboxamide-co-polydimethylsiloxane (Co-Py-PDMSs) and cobalt(II)-bipyridinedicarboxamide-co-polydimethylsiloxane (Co-Bipy-PDMSs) polymer−metal complexes were prepared by complexation between Py-PDMSs or Bipy-PDMSs ligands and cobalt(II); the metal content in these complexes varied from 0.09 to 2.41 wt %. The Co II binding patterns (the Co−N Py and Co−O coordination in Co-Py-PDMSs and Co−N Bipy in Co-Bipy-PDMSs) were established by UV−vis and IR methods and by comparison with model Co II complexes exhibiting relevant O,N,O-and N,N-coordination environments, respectively. The mechanical properties of the polymer−metal complexes were controlled by the coordination of Py-PDMSs or Bipy-PDMSs to Co II at various metal-toligand molar ratios (1:(1−6)) and by the variation of the polydimethylsiloxane unit length (M n : 850−900, 5000, or 25 000 g•mol −1 ). Utilization of the chelated Py-PDMSs and Bipy-PDMSs polymer ligands, which are capable of tri-or bidentate binding of Co II , led to (2−4)-fold increases in tensile strength (up to 1.75 MPa) and much higher elongation at break ((2−3)-fold increase up to 2100%) compared with the previously reported Co II -based polymer− ligand systems featuring monodentate ligation entities. Changing the main-chain ligand from Py-PDMSs to Bipy-PDMSs led to an increase in tensile strength of (2−4)-fold in comparison with Py-PDMS and a lower hysteresis (4%). The room temperature selfhealing efficiency was up to 96% for Co-Py-PDMSs and 40% for Co-Bipy-PDMSs, as measured for a polydimethylsiloxane unit with M n = 25 000 g•mol −1 .

Light-excited flexible and self-healing luminescent polymers have attracted extensive attention for developing advanced color-emitting films. Luminophores on the base of lanthanide(III)-incorporating polysiloxanes exhibit a high photoresponse and can be applied for controlled color lighting in flexible device applications. We present red-, green-, and blue-emitting Eu 3+ , Tb 3+ , and Tm 3+ -bipyridinedicarboxamide-co-polydimethylsiloxanes (Ln-Bipy-PDMS) produced with a two-step procedure of polycondensation and complexation. Bipyridinic ligands provide formation of coordinatively saturated complexes of lanthanide ions and strong photoluminescence (PL) in the case of Eu 3+ and Tb 3+ . The thin Ln-Bipy-PDMS films are studied as ultraviolet-light converters, which can be mechanically stacked one above another to achieve the desired color. We demonstrate that these stacks can have intense PL in the spectral range from green to yellow and red. Due to the structural features, Ln-Bipy-PDMS also demonstrate a relatively high tensile (approximately 1.5 MPa) and elongation at break (approximately 185%) and non-autonomous self-healing on heating. The self-healing properties of Ln-Bipy-PDMS enable the stacking of films into monoliths with the required color of PL. Such systems do not require any synthesis stages, and a one-healed monolith film possesses two luminescence colors.

cis - and trans -Isomers of the platinum(II) nitrile complexes [PtCl 2 (NCR) 2 ] (R = NMe 2 , N(C 5 H 10 ), Ph, CH 2 Ph) were examined as catalysts for hydrosilylation cross-linking of vinyl-terminated polydimethylsiloxane and trimethylsilyl-terminated poly(dimethylsiloxane- co -ethylhydrosiloxane) producing high quality silicone rubbers. Among the tested platinum species the cis -complexes are much more active catalysts than their trans -congeners and for all studied platinum complexes cis -[PtCl 2 (NCCH 2 Ph) 2 ] exhibits the best catalytic activity (room temperature, c = 1.0 × 10 −4 mol/L, τ pot-life 60 min, τ curing 6 h). Although cis -[PtCl 2 (NCCH 2 Ph) 2 ] is less active than the widely used Karstedt’s catalyst, its application for the cross-linking can be performed not only at room temperature ( c = 1.0 × 10 −4 mol/L), but also, more efficiently, at 80 °C ( c = 1.0 × 10 −4 –1.0 × 10 −5 mol/L) and it prevents adherence of the formed silicone rubbers to equipment. The usage of the cis - and trans -[PtCl 2 (NCR) 2 ] complexes as the hydrosilylation catalysts do not require any inhibitors and, moreover, the complexes and their mixtures with vinyl- and trimethylsilyl terminated polysiloxanes are shelf-stable in air. Tested catalysts do not form colloid platinum particles after the cross-linking.