Green emission enhancement of BaSiO:Eu phosphor via Gd co-doping and charge compensation.

A series of new green-emitting BaSiO:xEu, yGd, yR (R = Li, Na or K) phosphors were synthesized by the solid-reaction method. X-ray diffraction (XRD) and fluorescence spectrophotometer are utilized to characterize the crystal structure and luminescence properties of the as-synthesized phosphors, respectively. The XRD patterns reveal that the doping of Gd, Eu and R ions have no significant influence on the BaSiO phase. The green emission of Eu ion associated with 4f5d → 4f can be obtained by 396 nm UV excitation source, which match well with the emission wavelength of UV-LEDs chip (380-420 nm). Moreover, the effect of charge compensator ions (Li, Na or K) on the luminescence intensity of (Ba, Gd)SiO:Eu phosphors were also investigated. When introducing the Li ions into the (Ba, Gd)SiO host lattices, the as-prepared phosphors show the strongest emission. The emission intensity of BaSiO:0.04Eu, 0.005Gd, 0.005Li is about 1.39 times than that of BaSiO:0.04Eu. Furthermore, the mechanism of energy transfer and concentration quenching of BaSiO:xEu, 0.009Gd, 0.009Li phosphors are also discussed. [ABSTRACT FROM AUTHOR]