Influence of activation energy on charge conduction mechanism and giant dielectric relaxation of sol-gel derived C3H7NH3PbBr3 perovskite; Act as high performing UV photodetector

Abstract

This work contains an extensive study on temperature dependent complex dielectric behavior over 4 Hz≤ f≤ 8 MHz of a promising hybrid perovskite, propylammonium lead bromide. The structural, as well as morphological property of this sol-gel derived sample have been analyzed with the help of XRD and SEM respectively. The obtained energy band gap and thermal stability study ensure the capability of this material in device fabrication. Possessing a wide band gap, this perovskite fascinatingly serves as a UV photodetector. The individual impact of grain and grain boundary over the entire resistance has been resolved by Maxwell – Wagner Cole–Cole model. This material holds an amazing property; giant dielectric constant near room temperature at low frequency limit which escalates rapidly in the influence of thermal effect. Modified cole – cole plot assures that both space and free charge conductivities ascend with temperature. The asymmetrical nature of the imaginary part of electric modulus is analyzed by Kohlrausch – Williams – Watts which confirms its non – Debye nature diminishes with rising temperature. The thermally triggered AC conductivity follows Jonscher’s power law and is emphasized with the jump relaxation model. The bulk conductivity of the sample depends on temperature and is elucidated with variable range hopping of localized charge carriers. Activation energy plays a key role in the ionic conduction mechanism within the sample, described elaborately. The overall substantial studies on its application as UV detector and different dielectric properties of this sample construct the basis of appreciable acceptability of the sample in energy harvesting.