In this article, 5 at.% Yb:Lu 2 O 3 transparent ceramics were fabricated by vacuum sintering combined with hot isostatic pressing (HIP) posttreatment using co-precipitated nano-powders. The influence of precipitant molar ratio, ammonium hydrogen carbonate, to metal ions (AHC/M 3+ , R value) on the properties of Yb:Lu 2 O 3 precursors and calcined powders was investigated systematically. It was found that the powders with different R value calcined at 1100°C for 4 hours were pure cubic Lu 2 O 3 but the morphologies of precursors and powders behaved differently. The opaque samples pre-sintered at 1500°C for 2 hours grew into transparent ceramics after HIP posttreatment at 1750°C for 1 hour. The final ceramic with R = 4.8 showed the best optical quality with the in-line transmittance of 79.7% at 1100 nm. The quasi-CW laser operation was performed at 1034 nm and 1080 nm with a maximum output power up to 8.15 W as well as a corresponding slope efficiency of 58.4%.
Uniform and well-defined Lu 2 O 3 and Lu 2 O 3 :Eu 3+ microarchitectures have been successfully synthesized via a green and facile ionic liquid-based hydrothermal method followed by a subsequent calcination process. Novel 3D micro-rodbundles and 1D microrods of Lu 2 O 3 and Lu 2 O 3 :Eu 3+ were controllably obtained through this method. X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and photoluminescence spectra were used to characterize the micromaterials. The proposed formation mechanisms have been investigated on the basis of a series of SEM studies of the products obtained at different hydrothermal durations. The results indicated that hydrothermal temperature and the ionic liquid-tetrabutylammonium hydroxide were two key factors for the formation as well as the morphology control of the Lu 2 O 3 and Lu 2 O 3 :Eu 3+ microarchitectures.