Doping effects of transition metals and rare earth ions in KMPO4:Ln ceramics: Implications for electrical and microstructural characteristics

Abstract

A series of ceramic materials with the chemical formula KMPO4 (M = Mg, Mn, Ni, Cu) and KMgPO4:Ln (Ln = Nd, Dy, Er) were obtained by the solid-state reaction method. Analysis via X-ray diffraction (XRD) revealed that these materials exhibited distinct crystal systems, depending on the divalent used metal. Infrared spectroscopy (IR) was employed to characterize the P–O bonds within the coordination polyhedral. Energy-Dispersive X-Ray (EDX) analysis confirmed the presence of the constituent elements and the quantity of dopants incorporated into the crystalline structure. Complex Impedance Spectroscopy (CIS) was utilized to evaluate the conductivity of these compounds. Notably, conduction in these materials is predominantly cationic within the temperature range of 513–653K, occurring as ions migrate due to thermal agitation. Materials doped with rare earth ions demonstrated low activation energy values, making them promising candidates for use[n electrochemical applications, particularly in potassium-based batteries.