Color-tunable emission and energy transfer investigation in Sr3Y(PO4)3:Ce3 +,Tb3 + phosphors for white LEDs

• Energy transfer from Ce3 + to Tb3 + in Sr3Y(PO4)3 was investigated carefully.
• The intensity of Tb3 + emission can be greatly enhanced by co-doping with Ce3 +.
• Emission colors vary from blue to green by adjusting the Ce3 +/Tb3 + ratios.

A novel color-tunable phosphor Sr3Y(PO4)3:Ce3 +,Tb3 + was synthesized through solid-state reaction method. Several techniques, such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy, were used to investigate the obtained phosphors. Results of luminescence spectra and decay time measurements revealed that an efficient energy transfer occurred from Ce3 + to Tb3 + via a dipole–dipole mechanism, where Ce3 + exhibited a strong excitation band in the near-ultraviolet region. CIE chromaticity coordinates were tuned from deep blue (0.162, 0.090) to green (0.230, 0.411) by adjusting the relative concentrations between Ce3 + and Tb3 + ions. Results revealed that the as-synthesized phosphors had color-tunable characteristics and can be used as promising materials in the field of phosphor-converted white light-emitting diodes.

Figure optionsDownload as PowerPoint slide