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The synthesis and the microstructural, morphological, optical characterization of poly (N-pentenyl-carbazole) are reported. The obtained polymer present a stereoregular isotactic microstructure and is cristalline with a Tm of 138°C. Photoluminescence analysis of chlorobenzene polymer films, having high homogeneity and low roughness, show that PPK emits in a broad spectrum range 350-600 nm.

Organic thin-film transistors (OTFTs) with bottom-gate top-contacts architecture have been fabricated on glass substrates using solution-processed TIPS-pentacene (triisopropylsilyl pentacene) as semiconductor and cross-linked PVP (poly(4-vinylphenol)) as insulator, with Gold contacts evaporated through shadow masks. Applying constant electrical stress for short time on both gate and drain, an increase of drain current respect just finished devices have been observed in output and transfer characteristics.

High conductive and transparent nanocomposite films consisting of poly(3,4-ethylenedioxythiphene):poly(4-styrenesulfonate) (PEDOT:PSS) doped with dimethyl sulfoxide (DMSO) and double-walled carbon nanotubes functionalized with carboxylic groups (c-DWCNTs) were spin-coated and their electrical (four-point measurement), optical (UV-Vis spectroscopy), morphological (SEM, AFM) and structural (Raman) properties were investigated. Thin films of c-DWCNT/DMSO-PEDOT:PSS resulted more conductive (950 S/cm) in comparison with the pristine DMSOPEDOT: PSS films (700 S/cm).

In this paper, the electrical and optical properties of organic light emitting diodes (OLEDs) are analyzed, deriving the devices limits at high applied electric fields. In particular, for different device thicknesses, it is possible to conclude that the optical breakdown can be attributed to a surface phenomenon, that the temperature of electrical failure is significantly different from the optical one, that the two phenomena of failure are markedly similar at different thicknesses and that there is a maximum field beyond which the thin cathode may be destroyed due to phenomena not agreeable to thermal events.

Metal-insulator-semiconductor (MIS) capacitors based on pentacene semiconductor and CYTOP polymeric dielectric were realized and characterized by capacitance-frequency measurements (C-F) under dark and light conditions at different aging times. The devices showed good responses under light radiation at zero time and a strong degradation of the performances during the time due to a modification of the impedance of the dielectric layer.

In this work, the photophysical proprieties of 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) dye in the poly-vinylcarbazole (PVK) matrix are analyzed with a particular attention to the energy transfer processes between the matrix and the dye. PVP films with varying weight percent (from 1 to 8 wt%) of DCM have been fabricated. The presence of DCM induces a red shift in the emission spectra of the blend and a quenching effect in the excitons lifetime increasing the concentration of the dopants. These two phenomena have been studied in terms of energy processes inside the blends.