Preparation and Luminescent Properties of Ca-5(PO4)(3)Cl:Eu2+ Phosphors by a Solid-State Reaction Method

Ca-5(PO4)(3)Cl:Eu2+ powders were synthesized by a solid-state reaction method using CaCl2 as a chlorine source. CaCl2 effectively contributed to both the solid-state reaction and luminescent properties, acting as a flux and a chlorine source simultaneously. With a small amount of CaCl2, the beta-tricalcium phosphate(beta-TCP) phase coexisted with Ca-chlorapatites (CCAp), and then it decreased and finally disappeared with increasing CaCl2, resulting in a CCAp single phase. Photoluminescence (PL) spectra of CCAp exhibited a single blue emission at 460 nm under the excitation of 370 nm. PL intensity was correlated with the phase ratio of beta-TCP/CCAp. Excess Cl evaporation at the high firing temperatures above 1100 degrees C dominantly caused the abrupt decrease in PL intensity. (C) 2009 The Electrochemical Society. [DOI: 10.1149/1.3122669] All rights reserved.