Effects. of doping concentration and co-doping with cerium on the luminescence properties of Gd3Ga5O12:Cr3+ for thermometry applications

Abstract The accuracy of surface temperature measurements using thermographic phosphors relies on an extensive knowledge of the temperature-dependent properties of the phosphor. This paper addresses the effects of doping concentration and co-doping with cerium on the luminescence properties of the Gd 3 Ga 5 O 12 :Cr 3+ phosphor. High-crystallinity Gd 3 Ga 5 O 12 :Cr 3+ ,Ce 3+ powder samples (GGG:Cr,Ce) with different Cr 3+ and Ce 3+ concentrations were synthesized, and their luminescence spectra as well as their decay lifetime properties were characterized after UV laser excitation. Results revealed that the concentration quenching decreases the luminescence lifetime at concentrations above 0.5 mol% Cr 3+ while the emission spectrum remains independent of the Cr 3+ concentration. Co-doping with small amounts of Ce 3+ improves the temperature-dependent luminescence characteristics by reducing the afterglow and producing fairly mono-exponential luminescence decays without changing the lifetime.