Synthesis, Characterization and Dielectric Properties of Novel Metal Oxide - Phthalocyanine Nanocomposites

Document Type : Original Article

Authors

1 Physical Chemistry Department, National Research Center, Dokki, Giza, Egypt.

2 Physical Chemistry department, NRC, Dokki, Giza, Egypt.

Abstract

Organic and metal-organic polymers which have electrical properties have opened up a promising field in material science and engineering. Phthalocyanine (H2Pc) and metal oxide– phthalocyanine (MO-Pc) where (MO = ZnO, NiO, FeO and CoO) were prepared by urea fusion technique. The prepared composites were identified by means of Fourier transform infrared spectroscopy (IR) and X-ray diffraction (XRD). The XRD data indicate that the ZnO-Pc and NiO-Pc are highly crystalline and particle sizes are 13 nm and 9 nm respectively. The dielectric properties including dielectric constant ɛ' and dielectric loss ɛ'' of the prepared composites were calculated from the experimental capacitance values in the frequency range 100 Hz to 5MHz and in the temperature range of 25oC to 120oC. Generally, ɛ' are found to be decreased with increasing frequency and increase with increasing temperature. It is obvious that, appearance of peak for each MO in the dielectric loss suggests the presence of relaxing dipoles in the MO-Pc nanocomposites. The relaxation time τ, activation enthalpy ΔH and the entropy change ΔS of the prepared composites were calculated. The obtained data were correlated to the nature of doping metal oxide.

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