Photoluminescence of Tb 3+/Ce 3+ co-doped aluminum oxynitride powders

Abstract

Aluminum oxynitride(AlON) phosphors co-doped by Tb 3+ and Ce 3+ were synthesized by nitridation of the precursor which was co-precipitated from Al(NO 3) 3 solution and nanosized carbon black at 1750 °C for 2 "hrs" in flowing nitrogen atmosphere. The obtained AlON based powders were composed of polycrystalline spinel typed particles with sizes in the range of 1–3 μm. Under an excitation of 275 nm, it was found that co-doping of Ce 3+ could drastically enhance the luminescence of AlON:Tb 3+ powder by energy transfer. The product with 0.5 mol% Ce 3+ and 0.67 mol% Tb 3+ exhibited a strong broad green emission at 540 nm. The critical quenching concentration of Tb 3+ in AlON:0.5 mol% Ce 3+/xmol% Tb 3+ phosphor was determined to be 0.67 mol%. It was supposed that the mechanism of concentration quenching of Tb 3+ in AlON:0.5 mol% Ce 3+ xmol% Tb 3+ phosphor was dipole–dipole interaction.