Hopping conductivity in polymer matrix-metal particles composites

Charge transport properties, such as the temperature dependent dc conductivity and the frequency dependent conductance, of polymer matrix-metal particles composites, are investigated in the present study. Dc and ac conductivity is examined with varying parameters the filler content, temperature and the frequency in the case of ac field. The examined systems, though they are characterized as dielectrics, exhibit considerable conductivity, which alters by several orders of magnitude with temperature and frequency. The temperature and frequency dependence of conductivity gives evidence for the charge carriers transport mechanism via the occurred agreement of experimental results with the employed hopping models (variable range hopping model and random free-energy barrier model). (c) 2005 Elsevier Ltd. All rights reserved.