Electrical conductivity of polyazomethine/fullerene C60 nanocomposites

We prepared the polyazomethine/fullerene C-60 nanocomposites varying in C-60 loading. With a broadband dielectric relaxation spectrometer, we measured their electrical conductivity sigma(m) being a sum of dc conductivity sigma(dc) and ac conductivity sigma(ac). A small C-60 content (0.25 and 0.5 wt.%) was shown to decrease sigma(dc), whereas a larger amount of C-60 (2.5 wt.%) was found to increase sigma(dc) of the nanocomposite. The temperature dependences of sigma(ac) were described with the Arrhenius equation, while the frequency dependences of sigma(ac) were characterized with a power function. The correlated barrier hopping was accepted as the most suitable mechanism to explain the sigma(ac) behavior of the nanocomposites. (C) 2016 Elsevier B.V. All rights reserved.