A Green-Emitting Phosphor Sr3La(PO4)(3):Ce3+,Tb3+ with Efficient Energy Transfer for Fluorescent Lamp

Abstract

Green-emitting phosphors of Sr3La(PO4)(3):Ce3+,Tb3+ have been synthesized by a solid-state reaction. The energy transfer from Ce3+ to Tb3+ is a resonant type via a dipole-dipole mechanism with an energy-transfer critical distance of 7.6 angstrom. By utilizing the principle of energy transfer and appropriate tuning of activator contents, we have also made an attempt to observe a strong green emission performance displayed by this phosphor for use as a coating material on compact fluorescent lamps (CFLs). The results clearly indicate that the luminous efficiency based on Sr-3(La0.67Ce0.08Tb0.25)(PO4)(3) was found to be 69 lm/W. The good luminous efficiency and lumen maintenance (2000 h, 91.8%) of the green-emitting CFL demonstrate that this phosphor can be suitable for application on a short UV fluorescent lamp. Additionally, the Sr-3(La0.67Ce0.08Tb0.25)(PO4)(3) green phosphor has advantages of environmental friendliness and low cost. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3384662] All rights reserved.