INFRARED-SPECTRA AND ELECTRICAL-CONDUCTIVITY OF THE SOLID-SOLUTIONS XSRO-X)EU2O3, -THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.08((1)

The solid solutions xSrO+(1-x)Eu2O3 were synthesized at 1050 degrees C in air. Their phases were investigated by XRD and IR spectroscopy. Th rough XRD, we observed that the lattice parameters increased with incr easing amount of SrO. In particular, effective replacement of Eu by Sr for all solid solutions was identified by the peak shifts of the IR s pectra. With the addition of SrO, the vibration of pure Eu2O3, which i s normally observed at 528 cm(-1), is shifted to 532 cm(-1). The solid solutions show electronic n-type conductivity at oxygen partial press ures lower than 2X10(-3) atm above 720 degrees C owing to the singly a nd doubly effectively ionized oxygen vacancies. At oxygen partial pres sures higher than 2x10(-3) atm above 720 degrees C, the electrical con duction is p-type, owing to the triply effectively ionized europium va cancies.