Luminescence properties of Eu3+-doped Lanthanum gadolinium hafnates transparent ceramics.

Eu 3+ -doped Lanthanum gadolinium hafnates (La 0.8 Gd 1.2 Hf 2 O 7 ) transparent ceramics with different Eu 3+ concentration were fabricated by vacuum sintering. XRD results showed all the ceramics are cubic pyrochlore structure. The effects of annealing process on in-line transmittance and luminescence behavior of the Eu 3+ -doped La 0.8 Gd 1.2 Hf 2 O 7 transparent ceramics were investigated. Before annealing, the in-line transmittance of the ceramics was low and the luminescence intensity was weak. As Eu 3+ doping content increased, the transmittance as well as the luminescence intensity decreased. This was ascribed to oxygen vacancy and other defects in the ceramics resulted from the vacuum sintering. After annealing, the transmittance and luminescence intensity were raised, indicating the elimination of oxygen vacancy. Moreover, with the increase of Eu 3+ doping content from 1 at% to 10 at%, the luminescence intensity increased without concentration quenching. [ABSTRACT FROM AUTHOR]