Synthesis of high luminescence (Sr, Ba)₂SiO₄:Eu²⁺phosphor by gel-assisted freeze drying method using water soluble silicon compounds

Abstract

Phosphors of (Ba, Sr)₂SiO₄:Eu²⁺ (4%) with emission colors ranging from green to orange, which depends on Ba/Sr ratios, were synthesized by our originally developed gel-assisted freeze drying method using a unique water-soluble silicon (WSS) compound as a silicon source in combination with a flux treatment. All the samples with compositions of Ba₂SiO₄:Eu²⁺, Ba_0.6Sr_1.4SiO₄:Eu²⁺, Ba_0.4Sr_1.6SiO₄:Eu²⁺ and Sr₂SiO₄:Eu²⁺ were efficiently excited with a blue light (450 nm) with the corresponding emission maxima at 512, 550, 563, 581and 615nm, and their emission intensities were 2.4, 1.7, 1.7 and 1.1 times larger than that of one of the commercially available YAG:Ce³⁺phosphor, respectively.