Studies on Structural and Ionic Conductivity of Li2NiP2O7

Abstract

In this study, a solid-state method was employed to synthesize Li2NiP2O7. By analyzing the X-ray diffraction (XRD) data, the existence of a monoclinic-type structure with a single phase was verified using Rietveld refinement. The surface morphology of the samples was examined using scanning electron microscopy (SEM). Moreover, the electrical properties were measured using complex impedance spectroscopy (CIS) as a function of frequency (10 Hz to 7 MHz) at various temperatures (553–653 K). Impedance analysis was performed using an equivalent circuit model, which indicated the presence of a single semicircular arc. In addition, we investigated the intricate relationships between the electrical and structural properties of the materials, as well as the transport phenomena. Specifically, we explored the ion-hopping mechanism, which is governed by the movement of Li+ cations within the Li2NiP2O7 structure and is responsible for the conduction mechanism. Finally, it is important to note that our exploration of the Li2NiP2O7 compound revealed a noteworthy electrical conductivity of σ 573 = 1.23*10−2 Ω−1 cm−1. These findings underscore the potential suitability of this material for application as a promising cathode material for recheagable batteries.