(Tb3+, Eu3+)-Codoped Ga2O3 Phosphors: Synthesis and Photoluminescence Properties

摘要

(Tb3+, Eu3+)-codoped Ga2O3 crystallites, together with Tb3+/Eu3+ singly doped crystallites, were synthesized by metal-organic decomposition (MOD) and their material properties were studied in detail. The X-ray diffraction analysis indicated that only beta-phase Ga2O3 can be synthesized by the MOD and subsequent calcination at T-c >= 700 degrees C. Above similar to 900 degrees C, calcination treatment greatly reduced the Tb3+ green and Eu3+ red emission intensities. Therefore, the phosphor crystallites were mainly calcined at 800 degrees C. The phosphor properties were examined using photoluminescence (PL) analysis, PL excitation spectroscopy, and PL decay measurement. The Tb3+ and Eu3+ emission intensities in the Ga2O3: Tb3+, Eu3+ phosphors by excitation at lambda(ex) = 266 nm showed remarkable concentration quenching at >= 0.03 mol% (Tb3+) and >= 0.1 mol% (Eu3+), whereas those in the Tb3+/Eu3+ singly doped samples showed concentration quenching at >= 0.1 mol%. The concentration quenching in the (Tb3+, Eu3+)-codoped samples was confirmed by the PL decay measurements. The temperature dependences of the Tb3+ and Eu3+ emission intensities in the singly doped and codoped samples were measured at T = 20-450 K in increments of 10 K and analyzed by a simplified thermal quenching model. Discussion was made on the possibility of resonant energy transfer between Tb3+ and Eu3+ in the beta-Ga2O3 host. (C) 2016 The Electrochemical Society. All rights reserved.