Electrical characterization of AgNPs-PVA nanocomposites thin film-based heterojunction diode

Abstract

Abstract The purpose of this work is to study the results of electrical measurements carried out of nano metal-semiconductor heterojunctions based on Poly Vinyl Alcohol (PVA)to examine the possibilities of either an Ohmic contacts or rectifying behavior like a Schottky junction. The PVA doped silver nanoparticles (AgNPs-PVA)were confirmed and characterized by using x-ray Diffraction (XRD),Fourier-Transform Infrared Spectroscopy (FT-IR), Thermogravimetric analysis (TG) and Differential Scanning Calorimeter (DSC). A thorough investigation of the predominant conduction mechanism, dielectric relaxation, and current-voltage behavior of a polyvinyl alcohol (PVA)–Silver nanoparticles (AgNPs) nanocomposite film has been presented. With two activation energies, Ag nanoparticles have been demonstrated to improve the conductivity and dielectric permittivity of films. In the sample, a non-Debye type asymmetric behavior has been found, which may be analyzed using a modified Cole-Cole model. The temperature dependence of the a.c. conductivity σ ac and power law exponent s is reasonably interpreted by the Correlated Barrier Hopping (CBH) and Small Polaron Tunnelling (SPT) models at low and high frequency ranges, respectively. The junctions were created by spin coating and characterized of evaluated according to their I-V characteristics. Non-Ohmic electrical behavior was observed. The phenomenon supposed to be partly responsible for such nonlinearity is existence of thin barrier layer on the surface of dried polymer nanocomposites, through which charge carriers could pass by tunneling. This Schottky diode manufactured of an AgNPs-PVA nanocomposite was electrically characterized and investigated. However, deeper discussion will be necessary to illuminate all the circumstances leading to understand this behavior.