Charge Compensation and Enhanced Photoluminescence of Sr2SiO4:Eu3+, Li+ Phosphor

Abstract

A Eu3+activated strontium silicate phosphor was synthesized by solid-state reaction and Li+ion was added to balance the charge valence. X-ray powder diffraction analysis confirmed the formation of pure Sr2SiO4phase without second phase or phases of starting materials irrespective of the adding amount of Li+. Scanning electron microscopy showed large particle size and necking shape were obtained as the concentrations of Li+ions increase. In the PL studies, the excitation spectrum of Sr2SiO4:Eu3+,Li+phosphors exhibited a broad band in the UV region centered at about 270 nm attributed to charge transfer state (CTS) band. As the Li+ion concentration increased, the photoluminescence intensity of the red emission at 617 nm of Eu3+ions was enhanced. The results showed that Li+ion is a effective charge compensators used in Sr2SiO4:Eu3+phosphor.