Effect of doping Gd3+ on crystal structure and luminescent properties of Sr2SiO4:Eu2+ phosphor

Sr1.995–1.5xGdxSiO4:0.005Eu2+ phosphor series with x=0–0.08 mol for near-ultraviolet white light-emitting diodes (NUV w-LEDs) were synthesized via solid-state reaction method. XRD profile pattern and refinement results demonstrated that doping Gd3+ ions resulted in the phase transformation (β-Sr2SiO4→α'-Sr2SiO4). The photoluminescence spectrum of the sample with x=0 mol displayed two emission peaks centered at 470 and 525 nm. The two-peak spectra became one-peak spectra with the Gd3+ concentration increasing. Actually, the fitting results demonstrated that the one-peak spectra were still composed of two single emission spectra. The photoluminescence intensity was improved and the CIE chromaticity coordinates were adjusted via doping Gd3+.

Emission spectra of Sr1.995–1.5xGdxSiO4:0.005Eu2+ (x=0–0.08 mol) (a) and Gaussian fitting results (x=0–0.04 mol) (b)Figure optionsDownload as PowerPoint slide