Ag-based delafossite structure prepared by solid-state reaction: investigation of optical, electrical, and dielectric properties

Abstract

A^IB^IIIO₂ delafossite-type oxide materials have garnered considerable attention due to their significant physical and chemical characteristics, which have expanded their applications across various devices. This research examines AgCrO₂, highlighting its advantageous optical and electrical properties. X-ray diffraction (XRD) analysis confirms that the studied sample is well-crystallized in an orthorhombic structure with an Rm space group. The studied compound with a particle size of 1.75 μm was identified using transmission electron microscopy (TEM). The band gap energy was determined through UV-visible spectroscopy and was found to be 2.8 eV. A detailed analysis of Nyquist plots demonstrates the sensitivity of the material's electrical characteristics to variations in frequency and temperature. Applying Jonscher's power law to the AC conductivity as a function of temperature suggests that the conduction mechanism in the temperature range of 313 K to 613 K can be explained by the correlated barrier hopping (CBH) model, with an activation energy of 0.47 eV from 313 K to 493 K and 1.03 eV from 523 K to 613 K. Parameters such as the hopping distance R_ω and the density of localized states N(EF) were determined. The Kohlrausch–Williams–Watts (KWW) equation was employed to analyze the asymmetric curves of the electrical modulus. Additionally, the thermal variation of permittivity was interpreted using the Maxwell–Wagner effect as described by Koop's theory. Moreover, its high capacity and electrical conductivity highlight its potential for application in optoelectronic devices.