Vacuum sintering of highly transparent La1+xYb1+yZr2O7 ceramics with excess La and Yb contents

In this study, a series of transparent ceramics with chemical composition of La1+xYb1+yZr2O7 (x, y = 0.1-0.5) were successfully prepared by vacuum sintering using combustion synthesized powders. The effects of excess contents on the phase composition, microstructure and in-line transmittance have been studied. The detailed results indicate that the in-line transmittance increases at first and then decreases as La content be elevated. It was also determined that the highest in-line transmittance of La1+xYb1+yZr2O7 (x, y = 0.1-0.5) ceramics is 84.1 % at 1100 nm when the excess amount of co-doped La-Yb is 30 %. Compared with stoichiometric LaYbZr2O7 ceramic, the nonstoichiometric La1+xYb1+yZr2O7 (x, y = 0.1-0.5) ceramics exhibit much higher transparency. In addition, the high excess amount of La, Yb and co-doped La-Yb also shows effects on the phase composition and crystal structure.