Host Polyhedral Substitution and the Modification of the Luminescence Properties of Y2SiO5:Ce3+ Phosphor

Structural modification of the phosphor host plays a key role in the optimization of the luminescence properties of the optical materials, and it becomes the important research field for the exploration of the relationship between the solid structure and its property. The Y2SiO5 host is selected as the model to be substituted by the Si/Al or Si/P, and the [AlO4] and [PO4] tetragons are used to replace the [SiO4], so that a series of compounds with the chemical formula of Y1.95SiO5:0.05Ce(3+), Y1.95Si1-xAlxO5-xFx:0.05Ce(3+) (x=0.05, x=0.1, x=0.2, x=0.4, and x=1), Y1.95-yCaySi1-yPyO5:0.05Ce(3+) (y=0, y=0.02, y=0.04, y=0.06, y=0.08, and y=0.2) phosphors were designed and successfully obtained. XRD patterns showed that the diffraction peaks of both Y1.95Si1-xAlxO5-xFx:0.05Ce(3+) and Y1.95-yCaySi1-yPyO5:0.05Ce(3+) matched well with the standard patterns of Y2SiO5. Photoluminescence investigations indicated that the emission intensities had been increased to a great extent compared with that of Y2SiO5. A slight blue-shift was also observed in the emission spectra of Y1.95Si1-xAlxO5-xFx:0.05Ce(3+) and Y1.95-yCaySi1-yPyO5:0.05Ce(3+). Moreover, decay curves of Y1.95Si1-xAlxO5-xFx:0.05Ce(3+) and Y1.95-yCaySi1-yPyO5:0.05Ce(3+) confirmed that there are similar chemical environment for the Ce3+ luminescence.