Electrical Properties of Poly-N-Epoxypropylcarbazole/Vanadium Pentoxide Composite

M.H. Sayyad1, K. ul Hasan1, M. Saleem1, Kh.S. Karimov2, F.A. Khalid1, M. Karieva3, Kh. Zakaullah1 and Z. Ahmad1

1GIK Institute of Engineering Sciences and Technology, Topi, NWFP, 23460, Pakistan

2Physical Technical Institute of Academy of Sciences, Rudaki Ave, 33, Dushanbe, 734025, Tajikistan

3Tajik Technical University, Dushanbe 734000, Tajikistan

Abstract

In the present work the electrical properties of poly-N-epoxypropylcarbazole (PEPC) and vanadium pentoxide (V2O5) composite have been studied. The composite was formed by mixing of PEPC solution in benzene with V2O5 powder and stirring at room temperature. The composite solution was deposited on a dielectric substrate with copper electrodes and the Cu/PEPC-V2O5/Cu surface type film samples were fabricated. The Cu/V2O5/Cu samples were used as a reference where the films were deposited from the mixture of V2O5 powder in distilled water. Resistance-temperature relationship and voltage-current characteristics of the composite and V2O5 samples were studied by using conventional digital voltmeter and ammeter in the temperature range of 27-110C with an error of 0.5%. It was observed that the DC electrical conductivity, activation energy and non-linearity of voltage-current characteristics of the samples are temperature dependent. It was found that the temperature dependence of electrical conductivity of the V2O5 samples on the whole obeys T-1/4 law whereas the PEPC-V2O5 ones show visible deviations from that. The PEPC-V2O5 samples may be used as thermistors as the temperature coefficient of their resistance is large and at 27C is equal to -4.7%/C.