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Herein, we report the synthesis of organic–inorganic hybrids of polyaniline‐rGO‐ZnO (PRZ) ternary composite materials for a potential application in dye‐sensitized solar cell (DSSC). A facile all‐electrochemical method was adopted for the deposition of PRZ films on FTO‐coated glass substrate. The PRZ hybrid assembly was subsequently characterized by X‐ray diffraction, Raman spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry, and photoelectrochemical measurements. Further, the morphological and elemental composition features of PRZ were monitored by field emission SEM and EDX, respectively. Electrochemical impedance spectra suggest that the charge–transfer resistance for the ternary composite is distinctly decreased. The maximum conversion efficiency of DSSC with PRZ counter electrode reaches 2.84%, which is higher than that of polyaniline‐reduced graphene oxide (rGO) counter electrode. This ternary composite (PRZ) with organic–inorganic hybrid architecture showing an enhanced photoelectrochemical activity might be exploited in future as a promising material for application in next‐generation solar devices. [ABSTRACT FROM AUTHOR]

Abstract Herein, a photo-crosslinkable coumarin-containing polymer, poly(7-(4-vinyl-benzyloxyl)-4-methylcoumarin) or PVBMC, was prepared, and its physicochemical and electrical properties as a gate dielectric in organic electronic devices, such as organic thin-film transistor (OTFT) and inverter, was evaluated. The crosslinking of PVBMC by exposure to UV light (365 nm) over time was characterized using Fourier-transform IR and UV–visible spectroscopy. The measured capacitance of the cross-linked PVBMC thin film in a metal-insulator-metal-type capacitor was as high as 36.4 pF/mm2. Pentacene-based OTFT and load-type inverter with the cross-linked PVBMC gate dielectric were prepared, and their electrical responses were evaluated under ambient conditions. The OTFT showed dominant hole charge carrier transport behavior with a field-effect mobility of 1.52 × 10−1 cm2/Vs and negligible hysteresis. The load-type inverter based on the OTFT exhibited moderate static and dynamic switching responses to the applied electrical pulse. These results suggest the potential application of photo-crosslinked PVBMC as a gate dielectric in the fabrication of high-performance OTFT-based devices. Graphical abstract Image 1 Highlights • Photo-crosslinkable coumarin-based polymer (PVBMC) gate dielectric was synthesized. • Cross-linking of PVBMC involved [2 + 2] cycloaddition. • Cross-linked PVBMC high-density chain packing and increased hydrophobicity. • Device with cross-linked PVBMC gate dielectric had 30 × higher field-effect mobility with bias stability. [ABSTRACT FROM AUTHOR]

A series of dicyanomethylene-substituted polymers having Y-type molecular architecture were synthesized by Knoevenagel condensation reaction. The polymers were found to be soluble in organic solvents like tetrahydrofuran and chloroform. From gel permeation chromatography, the molecular weights of the polymers were found to be in the range of 15,300-33,800 g/mol. Thermal analysis showed that the polymers were stable up to 350 °C with glass transition temperature ( Tg) in the range of 129-212 °C. These polymers were found to form good optical quality films. The order parameter was calculated to be in the range of 0.01-0.48. Atomic force microscopy indicated prominent morphology changes due to alignment of dipoles after poling. By using Nd:YAG laser of 1064 nm, angular dependence and temperature dependence of second-harmonic generation intensity were investigated. The geometry optimization, shape of polymers, and restricted torsion angle between acceptor and donor substituents (push-pull system) were calculated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

A series of light-emitting hyperbranched poly(arylene ethynylene)s (HB-PAEs) were prepared by the Sonogashira coupling from bisethynyl of carbazole, fluorene, or dialkoxybenzenes (A2 type) and tris(4-iodophenyl)amine (B3 type). For comparison, two linear polymers (L-PAEs) of the HB analogs were also synthesized. The polymers were characterized by Fourier transform infrared, NMR, and GPC. The HB polymers showed excellent solubility in chloroform, THF, and chlorobenzene when compared with their linear analogs. The number-average molecular weight ( Mn) of the polymers determined from GPC was found to be in the range of 18,600-34,200. The polymers were thermally stable up to 298-330 °C with only 5% weight loss. The absorption maxima of the polymers were between 354 and 411 nm with optical band gap in the range of 2.5-2.9 eV. The HB polymers were found to be highly fluorescent with photoluminescence quantum yields around 33-42%. The highest occupied molecular orbital energy levels of the polymers calculated from onset oxidation potentials were found to be in the range from −5.83 to −6.20 eV. Electroluminescence (EL) properties of three HB-PAEs and one L-PAE were investigated with device configuration ITO/PEDOT:PSS/Polymer/LiF/Al. The EL maxima of HB-PAEs were found to be in the range of 507-558 nm with turn-on voltages around 7.5-10 V and maximum brightness values of 316-490 cd/m2. At the same time, linear analog of one HB-PAE was found to show a maximum brightness of 300 cd/m2 at a turn-on voltage of 8.2 V. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

The article presents the conducted study to analyze the effect of chromophore substituents on the optical and redox properties of the synthesized light emitting poly(p-phenylenevinylene) (PPV)-based conjugated-nonconjugated copolymers (CNCPs). PPVs are organic conjugated polymers that could be used as materials for light emitting diodes. Among the methods used in the study are the thin-layer chromatography, Fourier transform infrared (FTIR) spectroscopy, and gel permeation chromatography (GPC).