TITLE:
Large Redshifts in Emission and Excitation from Eu2+-Activated Sr2SiO4 and Ba2SiO4 Phosphors Induced by Controlling Eu2+ Occupancy on the Basis on Crystal-Site Engineering
AUTHORS:
Yasushi Sato, Hiroki Kuwahara, Hideki Kato, Makoto Kobayashi, Takaki Masaki, Masato Kakihana
KEYWORDS:
Photoluminescence, Red-Emitting Phosphors, Green-Emitting Phosphors, Orthosilicates, Crystal-Site Engineering
JOURNAL NAME:
Optics and Photonics Journal,
Vol.5 No.11,
November
25,
2015
ABSTRACT: The photoluminescence properties of Eu2+-activated α’-Sr2SiO4 and α’-Ba2SiO4 with a high Eu2+ concentration were investigated. In the case of Sr2-xEuxSiO4, emission was shifted from 585 to 611 nm with increasing the total Eu2+ concentration (x) from 0.1 to 0.8. This trend was similar to that in Ba2-xEuxSiO4, where the emission was shifted from 513 to 545 nm. The large redshifts in both the excitation and emission spectra were discussed in terms of the Eu2+ occupancies on two kinds of M sites and their local structural changes (M: Sr and Ba).