The influence of Sc/Lu ratio on the phase transformation and luminescence of cerium-doped lutetium scandium orthoborate solid solutions

• Published in: Journal of alloys and compounds 2011-01, Vol.509 (2), p.366-371
• Main Authors: Wu, Yuntao, Ding, Dongzhou, Pan, Shangke, Yang, Fan, Ren, Guohao
• Format: Article
• Language: English
• Subjects: Calcite; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder; Cross-disciplinary physics: materials science; rheology; Crystals; Density; Exact sciences and technology; Luminescence; Lutetium; Lutetium scandium orthoborate; Materials science; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phase transformation; Photoluminescence; Physics; Scandium; Solid solutions; X-rays
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2010.09.027

▶ Doping more than 10 at.% Sc 3+ can stabilize calcite phase of LuBO 3 up to 1550 °C. ▶ Luminescence properties of Lu 1− x Sc x BO 3:Ce solid solutions depend on the Sc/Lu ratio. ▶ Luminescence properties of Lu 1− x Sc x BO 3:Ce solid solutions depend on the Ce/RE ratio. ▶ Integrated intensity of (Lu 0.5Sc 0.5) 0.995Ce 0.005BO 3 crystal can achieve 27% of LYSO:Ce crystal. ▶ Lu 1− x Sc x BO 3:Ce could be a potential scintillator in X-ray or γ-ray detection technology. The dependence of structural characteristics of cerium-doped lutetium scandium orthoborate (Lu 1− x Sc x )BO 3:Ce solid solutions on Sc/Lu ratio was investigated. It was found that the calcite phase of LuBO 3 can be stabilized up to 1550 °C at least when the n(Sc)/ n(Lu + Sc) ratio was ≥10 at.%. The closed correlations between Sc 3+ or Ce 3+ molar ratio in the host and luminescence mechanism were discussed in detail. Based on the requirements of steady phase structure, better luminescence efficiency and higher density, the reasonable n(Sc)/ n(Lu + Sc) and n(Ce)/ n(RE) ratio should be in the range of 30–50 at.% and 0.3–0.5 at.%, respectively. A modified composition, (Lu 0.5Sc 0.5) 0.995Ce 0.005BO 3 solid solution, was selected to grow single crystal. Its X-ray excited luminescence intensity can be as high as about 27% of LYSO:Ce standard crystal and the effective lifetime is round 20.1 ns. Hence, the cerium-doped lutetium scandium orthoborate crystal is a promising scintillator for X-ray detection or γ-ray detection.