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The electrical properties of films of a new ternary nanocomposite – the dielectric polymer polyvinylidene fluoride (PVDF), the conducting polymer polyaniline doped with dodecylbenzenesulfonic acid (PANI), and multi-walled carbon nanotubes (MWCNTs, 0–15 wt.%) – have been studied. Based on the results of electrical resistance, R, experiments in a wide temperature, T, interval of 4.2–300 K, it is shown that, at low temperatures, the charge transfer in the nanocomposites with the indicated MWCNT contents takes place via the tunneling of charge carriers between localized states and following the mechanism of variable-range hopping conductivity, R ∼ exp[(T0/T)1/2]. It is found that the characteristic temperature T0 and the temperature interval of the hopping conductivity depend on the MWCNT content. In particular, the increase of the MWCNT content in the nanocomposite films lowers the characteristic temperature T0 by two orders of magnitude and narrows the temperature interval, where the hopping conductivity is observed, with the most pronounced changes occurring within an MWCNT content interval of 5–7.5 wt.%., У данiй роботi представлено результати дослiдження електричних властивостей плiвок нових тернарних нанокомпозитiв дiелектричного полiмеру полiвiнiлiденфториду (ПВДФ), провiдного полiмеру полiанiлiну, допованого додецилбензолсульфоновою кислотою (ПАНI), з рiзним вмiстом мультистiнних вуглецевих нанотрубок (МСВНТ). На основi результатiв дослiджень електричного опору нанокомпозитiв у широкому iнтервалi температур 4,2–300 К показано, що при низьких температурах для нанокомпозитiв iз вмiстом МСВНТ 0–15 мас.% перенесення електричних зарядiв вiдбувається за рахунок тунелювання носiїв заряду мiж локалiзованими станами вiдповiдно до механiзму стрибкової провiдностi зi змiнною довжиною стрибка R ∼ exp[(T0/T)1/2]. Встановлено, що величина характеристичної температури T0 i температурний iнтервал стрибкової провiдностi залежать вiд вмiсту МСВНТ. Збiльшення вмiсту МВСНТ у плiвках нанокомпозитiв вiд 0–15 мас.% приводить до зменшення характеристичної температури T0 на два порядки i звуження температурного iнтервалу, в якому спостерiгається стрибкова провiднiсть, причому найбiльш вираженi змiни вiдбуваються в iнтервалi вмiсту МСВНТ 5–7,5 мас.%.

International audience; One of the major challenges of printed electronics is to develop materials for flexible devices. Among these latter, antennas occupy a place of choice because of the new applications which are emerging. In this paper a flexible antenna based on a new nanocomposite, Polyaniline (PANI) charged by nanopowder of Iron-Nickel (Fe-Ni), operating in dual-band ([2.4-2.48] and [5.15-5.825] GHz) is proposed. This antenna, triangular/circular shaped with a coplanar waveguide (CPW) feeder to achieve wideband performance is printed on a 130μm thick Kapton® substrate. The nanocomposite fabricated (PANI/Fe-Ni), whose morphology was studied via scanning electron microscopy, has a conductivity of 9600 S/m. The performance of the antenna is analyzed through simulations and measurements which demonstrate a good agreement between each other. A maximum gain of 2.8 dBi for a 90μm thick nanocomposite is obtained. © 2019 European Association on Antennas and Propagation.

International audience; This paper presents the simulation and realization of a patch antenna made of composites based on Polyaniline (PANI) and carbon nanotubes (CNT). The antenna is designed to work at the frequency of 4.5 GHz; the dielectric substrates used is Rogers RT/duroid 5870 which has a dielectric permittivity of 2.35 and a loss tangent of 0.0012. The conductive polymer used has a conductivity of 4500 s/m, the carbon nanotubes used are multiwall carbon nanotubes. Simulation results show an antenna gain of 5.3dBi for PANI thickness of 70 μm. © 2014 European Association on Antennas and Propagation.

Nanocrystallin CdS films with controlled stoichiometry deposited by CSVS were investigated by meth-od of the current-voltage characteristics in ITO/CdS /In structures. It was shown that in the case of cadmi-um excess (S Cd) charge flow mechanism is deter-mined by monomolecular recombination. In the band gap of CdS with excess of cadmium there was detect-ed localized states with energy Et = 0.514 ± 0.026 eV, while in the material with Excess sulfur there are two localized states with energy Et1 = 0.514 ± 0.026 eV and Et2 = 0.700 ± 0.026 eV. Full concentration of lo-calized states is more than 2·1021 m-3 – 5·1022 m-3. Dependence of injection in parameters and nature of in-jection in the structures based on nanostructured CdS films on their stoichiometry was determined When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35240

Microwave absorbing properties of hybrid nanocomposites of Fe3O4 nanoparticles with carbon nanotubes and polyaniline (PANI) doped with dodecylbenzenesulfonic acid have been studied. It has been found that the the addition of nanostructured components increases the absorbtion of the nanocomposites. Moreover, CNTs affect the absorbtion in high frequency range, and Fe3O4 nanoparticles – in low frequency range. Introduction of conductive PANI into the matrix enhances the influence of nanomaterials on the absorbance of the films. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34911

International audience