A Green-Emitting Phosphor Sr(3)La(PO(4))(3):Ce(3+),Tb(3+) with Efficient Energy Transfer for Fluorescent Lamp

Abstract

Green-emitting phosphors of Sr(3)La(PO(4))(3):Ce(3+),Tb(3+) have been synthesized by a solid-state reaction. The energy transfer from Ce(3+) to Tb(3+) 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)(La(0.67)Ce(0.08)Tb(0.25))(PO(4))(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)(La(0.67)Ce(0.08)Tb(0.25))(PO(4))(3) green phosphor has advantages of environmental friendliness and low cost. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3384662] All rights reserved.