Synthesis and characterization of La0.9Sr0.1Ga0.8Mg0.2O3−δ intermediate-temperature electrolyte using conventional solid state reaction

► Pure phase LSGM powder is prepared by solid state reaction at 1,400 °C. ► The prepared LSGM provides an excellent ionic conductivity of 0.08 S cm-1 at 800 °C. ► The LSGM powder has a fine particle size and narrower particle size distribute. ► The LSGM powder is suitable to fabricate dense electrolyte membranes (20-25 μm).