Electrical conduction mechanism and dielectric relaxation of bulk disodium phthalocyanine
A Q Alosabi, A.A. Al‐Muntaser, M.M. El-Nahass, A. H. Oraby
Abstract
Abstract AC conductivity and dielectric characteristics of disodium phthalocyanine (Na 2 Pc) in a pellet form were investigated in a frequency range from 45 Hz to 3.12 MHz and a temperature range from 303 to 423 K. The charge carrier transport mechanism was determined according to the correlated barrier hopping model (CBH). Also, the electrical parameters were estimated in light of this model. The thermal activation energy of AC conductivity decreases with increasing frequency. The behavior dependence of dielectric loss and dielectric constant on temperature and frequency was discussed. The behavior of dielectric loss was explained based on the Giuntini model. The maximum value of barrier height, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">W</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">M</mml:mi> </mml:mrow> </mml:msub> <mml:mo>,</mml:mo> </mml:math> was obtained to equal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>0.38</mml:mn> <mml:mspace width=".25em"/> <mml:mi>eV</mml:mi> <mml:mo>.</mml:mo> </mml:math> The results showed that the type of relaxation mechanism is a non-Debye one. The activation energy is calculated for dielectric relaxation to be <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>0.36</mml:mn> <mml:mspace width=".25em"/> <mml:mi>eV</mml:mi> <mml:mo>.</mml:mo> </mml:math>