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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.%.

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