Charge Compensation and Enhanced Photoluminescence of Sr2SiO4:Eu3+, Li+ Phosphor
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 Sr2SiO4 phase 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.
H. Y. Chen et al., "Charge Compensation and Enhanced Photoluminescence of Sr2SiO4:Eu3+, Li+ Phosphor", Advanced Materials Research, Vols. 343-344, pp. 106-111, 2012