Improvement of photoluminescence properties and thermal stability of Y 2.9 Ce 0.1 Al 5 − x Si x O 12 phosphors with Si 3 N 4 addition

Abstract

A series of Si3N4 doping Y2.9Ce0.1Al5−xSixO12−3x/2N4x/3 phosphors were prepared by solid-state reaction in 95%N2–5%H2 reduced air ambience. The XRD characteristics plus Rietveld refinement results shows that the as-sintered powders are unique crystal phase with the same crystal structure of Y3Al5O12 (PDF No. 79-1891). The N element was not detected by the analysis of X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectrum (EDS). The photoluminescence spectra (PL & PLE) tests show that the exciting and emitting intensity of PLE & PL gradually increase due to the increase of Si3N4 concentration. Meanwhile, the phosphorescence decay times are prolonged from 45 ns (x = 0) to 78 ns (x = 0.3), under the monitor of 530 nm wavelength. The thermoluminescence tests (TL) confirm the thermal stability of as-phosphors with Si3N4 addition is much better than that of the pristine Y2.9Ce0.1Al5O12 phosphors.