Properties of La2-xSrxMo2-yWyO9-δ (x = 0-0.2, y = 0-0.3) synthesized via solid state reaction method
have been investigated. The results of XRD show a single phase of La2Mo2O9 after calcination at 950°C.
The phase transition temperatures from α to β phase of La2Mo2O9 and La1.9Sr0.1Mo2O9 occur around 557 °C
and 560°C, respectively. A substitute of 7.5 mol% of W6+ into Mo6+ can suppress the α phase. The average
grain size of sintered compositions increases with the amount of Sr but slightly decreases with an addition of
W. The conductivity value of La1.9Sr0.1Mo2O9 at 540°C is 6.75 x 10-3 S·cm-1. Above the phase transition
temperature, β- La2Mo2O9 shows the highest conductivity and its value at 700°C is 7.66 x 10-2 S·cm-1.