Synthesis of Ba2SiO4:Eu(2+) by a Hybrid Process and Its Luminescent Properties

Ba2SiO4:Eu(2+) powders were prepared using a sol-gel-combustion (hybrid) process with tetraethyl orthosilicate (TEOS) and colloidal silica (C-SiO2) as Si sources. The effects of the silicon sources and preparation conditions on phase formation and luminescent properties were investigated. The B2S:Eu(2+) powders synthesized with TEOS were composed of the irregular particles, whereas C-SiO2 was more conducive to uniform particle distribution for the Ba2SiO4:Eu(2+) powders, leading to the enhancement of the emission intensity. The photoluminescence spectra of the synthesized powders exhibited broad excitation bands spanning 250 to 450 nm, and strong green-emission bands, whose intensities and positions were heavily dependent on the concentration of Eu(2+) and Sr(2+) substituted for Ba(2+) in Ba2SiO4.