Temperature and frequency dependencies of AC and dielectric characterizations of copper tetraphenyl porphyrin thin films

Abstract

The AC conductivity and dielectric properties of the copper tetraphenyl porphyrin, CuTPP films have been investigated in the frequency range 42 Hz-5 MHz and in the temperature range 303-473 K. The AC conductivity of CuTPP is controlled by the correlated barrier hopping model. The activation energy for alternating current mechanism decreases with increasing frequency which confirms the hopping conduction to the dominant mechanism as compared with the DC activation energy. The dielectric constant É′ and dielectric loss É″ show noticeable dependence on frequency and temperature. The dielectric relaxation mechanism was explained on the basis of complex dielectric modulus. © 2013 Elsevier Inc. All rights reserved.