Synthesis and Luminescent Characteristics of(Ca4-x-y-zBaySrz)(PO4)2O:xEu2+ Phosphors as a Potential Applicationfor White-Light Emitting Diode

Abstract

A novel tunable red- to yellow- emitting phosphor, (Ca4-x-yzBaySrz)(PO4)2O:xEu2+ is reported that displays a broad emission from 500 to800nm, and its emission can be adjusted from red to yellow by changing Ba2+ andSr2+ doping concentration. X-ray powder diffraction analysis confirmed the phaseformation. Excitation and emission spectra, and concentration dependence ofemission intensity of the phosphor were investigated. The results showed that withincreasing Ba2+/Sr2+ concentration, the emission peak wavelength blue-shift from594 to 567 nm, and the color can be tuned from red to yellow. When single- phase(Ca2.95Ba0.5Sr0.5)(PO4)2O:0.05Eu2+ phosphor is pumped by a blue InGaN lightemittingdiode we obtain white light with color rending index between 80.0 and 89.0and color temperatures between 3500 and 5450 K, suggesting that this material iscompetitive as a color conversion material for solid state lighting.