Examining the consequences of calcium substitution on the physical properties and conduction mechanism of Y3GaO6.

The influence of calcium doping on the Y₃GaO₆ system was systematically investigated for electrochemical applications. The Y_3(1−x)Ca_3xGaO₆ (x = 0, 0.02, 0.04, 0.08, 0.12) ceramics compositions were prepared via conventional solid-state reaction route and their structural, electrical and electrochemical properties were investigated. The structural phase analysis revealed the formation of the orthorhombic phase with the Cmc2₁ space group. However, at higher concentrations of calcium doping, i.e. x > 0.02, a few secondary phases of Y₂O₃ and CaCO₃ were also observed. Impedance spectra suggest an increase in the total conductivity up to x = 0.02 of Ca doping, and a decrease in the conductivity was observed for the higher concentration of Ca substitution. The substitution of Ca with x > 0.02 not only increases the oxygen vacancies rather segregates the impurities along the grain boundaries. Consequently, the impurities have negative influence on both the grain and grain-boundary conductivities. Cyclic voltammetry and Chronoamperometry studies have also been performed to characterize the samples. [ABSTRACT FROM AUTHOR]