Fabrication and luminescent properties of fine-grained cerium-doped lutetium-yttrium oxyorthosilicate ceramics

Abstract

When compared to Lu2SiO5:Ce (LSO:Ce), cerium-doped lutetium-yttrium oxyorthosilicate solid solutions not only possess a similar density, but they also exhibit good scintillation properties (high light yield, short decay time and good energy resolution). Fine-grained Lu1.8Y0.2SiO5:Ce (LYSO:Ce) ceramics were fabricated via Spark Plasma Sintering (SPS) at a temperature of 1050 °C and an applied pressure of 100 MPa from a nano-sized LYSO:Ce powder. The average grain size of the sintered LYSO:Ce ceramics is 210 nm. To eliminate the oxygen vacancies that result from the sintering process, the sintered LYSO:Ce ceramics were subsequently annealed at 950 °C for 40 h in air. The in-line transmittance of the LYSO:Ce ceramics is 1.7% at 420 nm. The light yield of the annealed LYSO:Ce ceramics is 23,600 photons/MeV. It is suggested that SPS combined with annealing in air is a promising route to fabricate fine-grained LYSO:Ce ceramics with good scintillation performance.