Persistent luminescence in powdered and ceramic polycrystalline Gd3Al2Ga3O12:Ce

G Dosovitskiy,E Tret’Jak,V Mechinsky,A Dosovitskiy,A Fedorov,A Borisevich,M Korjik

doi:10.1088/1757-899x/169/1/012014

Abstract

This paper studies powders of Gd3Ga3Al2O12:Ce, a promising scintillator composition, as a possible object for express pre-characterization of scintillation kinetics and level of persistent luminescence. Garnet phase powders with uniform microstructure, consisting of 1-2 μm grains, were obtained by co-precipitation approach. It was shown, that both scintillation decay time and presence of persistent luminescence are influenced by both powder thermal treatment temperature and strong Ga deficit.

Highlights

Scintillator crystals and phosphors based on Ce-activated mixed garnets Gd3(Ga,Al)5O12 (GGAG) get increasing interest recent years [1], as they have promising applications on large markets, such as medical imaging
Strong persistent luminescence was observed for Gd3(Ga,Al)5O12:Ce ceramics and single crystals grown from raw materials of 99,995% or better purity [2,4]
In order to define an origin of persistent luminescence in Gd3Al2Ga3O12:Ce we have examined microstructure properties and scintillation kinetics of powder samples and ceramics, which are synthesized at temperatures up to 1600 °C

Summary

Introduction

Scintillator crystals and phosphors based on Ce-activated mixed garnets Gd3(Ga,Al)5O12 (GGAG) get increasing interest recent years [1], as they have promising applications on large markets, such as medical imaging. Strong persistent luminescence was observed for Gd3(Ga,Al)5O12:Ce ceramics and single crystals grown from raw materials of 99,995% or better purity [2,4]. Garnets with Al/Ga solid solution turned out to be promising materials for long glowing phosphors – strong persistent luminescence was observed in Y3(Ga,Al)5O12:Ce,Cr ceramic samples [5]. Certain homogeneity region was found for Gd2O3-Ga2O3-Al2O3 system as well [14], which means that scintillator could accommodate a lot of defects, caused by Ga deficit, and still comprise a single-phase garnet. In order to define an origin of persistent luminescence in Gd3Al2Ga3O12:Ce we have examined microstructure properties and scintillation kinetics of powder samples and ceramics, which are synthesized at temperatures up to 1600 °C. Ga volatility is much lower at these conditions, so powder composition could be better determined for crystals

Experimental

Results and discussion

Conclusions