Multiband Orange-Red-Emitting Phosphors SrY3SiP5O20: Eu3+ under Near-UV Irradiation

Abstract

The photoluminescence properties of silicon-based xenotime-type rare-earth phosphate as an orange - red - emitting phosphor material, SrY3SiP5O20:xEu3+SrY3SiP5O20:xEu3+ (0.2, 0.6, 1, 2, 3, 5, 10, and 15 mol %), are reported. The photoluminescence spectra of the silicon phosphate indicated the simultaneous occurrence of six predominant orange-red band emissions due to doubly split magnetic-dipole (D50–F71)(D50–F71) , electric-dipole (D50–F72)(D50–F72) , and unusual (D50–F74)(D50–F74) transitions under a near-UV wavelength excitation. The multiband emission of Eu3+Eu3+ at D50–F71,2,4D50–F71,2,4 is attributed to the odd-parity distortions of the Eu3+Eu3+ surrounding environment. With high Eu3+Eu3+ concentration, the phosphor has a strong excitation due to f–f transitions appearing at around 396 nm, which correspond to the popular emission line from a near-UV light-emitting diode (LED) chip. Thus, the intense orange-red emission of the silicon phosphate phosphors under near-UV excitation suggests them to be a potential candidate for white light generation by using near-UV LEDs.