IMPEDANCE SPECTROSCOPY AND DIELECTRICRELAXATION IN PHTHALOCYANINE THIN FILM

Türkçe

The sensing performance of 2(3),9(10),16(17),23(24)- tetrakis-[4-nitro-2-(octyloxy)phenoxy]phthalocyaninato zinc(II) thin film towards ammonia and the influence of relative humidity on it were studied. The results show that the exposure to ammonia gas leads to an increase in sensor current, which is unexpected because of the strong electron donating character of ammonia and p-type semiconductivity of phthalocyanine. This unexpected behavior is related to the change in electronic band structure of the Pc molecule. It was observed that relative humidity enhances the ammonia adsorption. Several adsorption kinetics model were employed to represent the ammonia adsorption on the sensor surface. Analysis of the experimental data indicated that a simple adsorption model can be used to represent our adsorption system.