Structure and electrical conductivity properties of K doped Sr1-xKx(Sr0.50Nb0.50)O2.75-delta complex perovskites

In the present study structural and electrical conductivity properties of complex perovskites with general formula Sr1-xKx(Sr0.50Nb0.50)O2.75-delta have been studied. Potassium is doped in the cuboctahedral Sr site Sr1-xKx(Sr0.50Nb0.50)O2.75-delta with different dopant concentrations such as x.=.0, 0.25, 0.50, 0.75 and 1. The structural and morphological properties of Sr1-xKx(Sr0.50Nb0.50)O2.75-delta were studied using Thermogravimetry (TG) analysis, x-ray diffraction (XRD) and Scanning electron microscopy (SEM). Electrochemical impedance spectroscopy (EIS) was performed to investigate the electrical properties. The effect of structural and morphological variations associated with the dopant concentration affecting the electrical conductivity behaviour of Sr1-xKx(Sr0.50Nb0.50)O2.75-delta complex perovskite oxides were studied in detail. The higher total conductivity was observed for 100% Kdoped (x = 1, 3.10 x.10(-5) S cm(-1) at 800 degrees C) and 25% K doped (x = 0.25, 2.02 x 10(-5) S cm(-1) at 800 degrees C) composition.