Influence of potassium doping on the structural, conduction mechanism, and dielectric properties of CaFe2O4

Abstract

The frequency and temperature-related dielectric relaxation and electrical conduction mechanisms in potassium-doped CaFe₂O₄ oxide ceramic were investigated in this study throughout a temperature range of 313–673 K. The synthesis of the KCaFe₂O₄ compound was accomplished through a solid-state reaction route. The X-ray diffraction pattern at room temperature confirmed that the ceramic KCaFe₂O₄ crystallizes in the orthorhombic system with the Pbnm space group. The EDX analysis proved the absence of external elements. The surface morphology of the samples was examined using scanning electron microscopy. The conduction mechanism, validated as CBH conduction, was examined using the temperature-dependent variation of Jonscher's power law exponent. Using Nyquist plots, we have effectively constructed a relevant equivalent circuit that encompasses the influences originating from both the grains and the grain boundaries. Furthermore, in KCaFe₂O₄, the induced dielectric relaxation from the non-Debye to Debye type model is demonstrated by the thermal analysis of M′′ (ω) and −Z′′ (ω) as a function of frequency.