Synthesis, morphological, dielectric studies and ionic conductivity of a sodium cerium diphosphate compound

Abstract

The NaCeP2O7 compound was successfully synthesized by a high-temperature reaction with the solid-state method. Analyzing the XRD pattern, of the studied compound, confirms the orthorhombic phase with the Pnma space group. The examination of SEM images reveals that the majority of grains are around 500 to 900 nm with a uniform distribution. As for the EDX analysis, all chemical elements were detected and found in their appropriate ratio. The curves of temperature-dependent imaginary modulus M" versus angular frequency reveal the presence of one peak at each temperature, proving that the dominant contribution is associated to the grains. The frequency dependence of the conductivity of alternating current is explained using Jonscher's law. The close values of the activation energies obtained from the jump frequency and extracted from the dielectric relaxation of the modulus spectra, as well from the continuous conductivity imply that the transport takes place by the Na+ ions hopping mechanism. The charge carrier concentration in the title compound has been evaluated and shown to be independent of temperature. The exponent s increases with the increase in temperature, this behavior proves that the non-overlapping small polaron tunneling (NSPT) is the appropriate conduction mechanism model.