Microstructure and luminescence properties of a Ce3+-doped Lu3Al5O12/Al2O3 eutectic grown by the micropulling down method

Inorganic scintillation materials have been widely used in several fields, such as high energy physics, nuclear medical imaging and industrial nondestructive inspection. In this work, a novel scintillation material, (CexLu1-x)(3)Al5O12/Al2O3 (Ce3+:LuAG/Al2O3) eutectic with different Ce3+-doping concentrations, was successfully grown by the micropulling down method at different pulling speeds. The effects of Ce3+-doping concentration and pulling speed on the microstructure and luminescent properties of the Ce3+:LuAG/Al2O3 eutectic were investigated. The eutectic has a typical garnet structure, and a "Chinese script" microstructure can be seen throughout the cross section. As the pulling speed increased, the grain size and the morphological appearance of the "Chinese script" microstructure decreases. The Ce3+:LuAG/Al2O3 eutectic shows a characteristic Ce3+ emission band centered at 508 nm, and the emission intensity increases with increasing Ce3+-doping concentration until the Ce3+-doping concentration reaches x = 0.01. The eutectic grown at a pulling speed of 1.7 mm/min shows maximum emission intensity, and the light yield of the (Ce0.01Lu0.99)(3)Al5O12/Al2O3 eutectic excited with X-ray at room temperature is approximately 64% of that of the (Ce0.01Lu0.99)(3)Al5O12 single crystal. The results reveal that the Ce3+:LuAG/Al2O3 eutectic has a potential application as an X-ray detector material. (c) 2019 Elsevier B.V. All rights reserved.