Crystal structure and photoluminescence properties of (Y1−xCex)4Si2O7N2

Oxonitridosilicate compounds with compositions of (Y1−xCex)4Si2O7N2 (x = 0-0.1) compounds have been synthesized. The relations of structure, photoluminescence properties and Ce content have been studied. These compounds have a broad band excitation covering from 350 to 450 nm and a broad band emission covering from 450 to 575 nm. There exist four different types of photoluminescence centers, which correspond to four different crystallographic sites accommodating the Ce3+ dopants in the lattice. The energy transfer among Ce3+ ions in different sites enhance with the increasing Ce content, leading to red-shift of the emission peaks and concentration quenching. The relationship between crystallographic sites of Ce3+ ions and luminescence properties is established. (Y1−xCex)4Si2O7N2 is a promising phosphor for use in white light-emitting diodes.