Development of novel scintillation and photo-conversion materials based on Gd3(Sc,Al,Ga)5O12:Ce single crystals grown by micro-pulling-down method

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2021-11, Vol.273, p.115395, Article 115395
• Main Authors: Markovskyi, A., Bartosiewicz, K., Chewpraditkul, W., Kim, K.J., Witkiewicz-Lukaszek, S., Zorenko, T., Yoshikawa, A., Zorenko, Yu
• Format: Article
• Language: English
• Subjects: Aluminum; Ce3; Cerium; Color temperature; Converters; Crystal growth; Crystal pulling; Crystals; Field strength; Gallium; Garnets; Phosphors; Scintillation; Scintillators; Single crystals; Thermal stability; white LEDs; White light
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2021.115395

[Display omitted] •Gd3(Sc,Al,Ga)5O12:Ce single crystals were grown by micro-pulling-down method.•Crystals are considered phosphor converters for WLED and scintillators.•Decrease of garnet band gap and crystal field strength with increasing Sc3+ and Ga3+ content.•Small amount of secondary perovskite phase was evidenced by the photoluminescence.•Energy transfer from perovskite phase to garnet phase is observed. Luminescence, scintillation and photoconversion properties of Gd3Al5−x−yScxGayO12:Ce crystals, grown by the micro-pulling-down method, were studied upon substitution of Al for Sc3+ and Ga3+ in the x = 1–2;y = 1–3 ranges. A decrease of the band gap and crystal field strength occurs in these garnets with increasing Sc3+ and Ga3+ content, resulted in blue-shift and reduced thermal stability of Ce3+ emission. Lowering of the scintillation light yield of crystals by two times and scintillation decay kinetic acceleration from 97 to 27 ns is observed at increasing Ga content in the y = 1–3 range. Sc and Ga admixing increases the number of deep charge traps, which additionally deteriorate of crystals scintillation performance. Application of Gd3Al5−x−yScxGayO12:Ce crystals as phosphor converters of white LED was considered. Increasing the Sc3+ and Ga3+ content in crystals leads to linear blue shift of the converter emission and results in increasing the color temperature of LEDs from neutral to could white light.