| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1494071 | Optical Materials | 2014 | 6 Pages |
•Li2SrGeO4:Ce3+/Tb3+/Dy3+ phosphors were synthesized by a solid-state reaction.•Li2SrGeO4:Tb3+/Dy3+ phosphors show green and yellow emissions respectively.•Ce3+ enhances the luminescence intensity of Tb3+/Dy3+ through energy transfer.•The energy transfer mechanism is demonstrated to be a dipole–quadrupole interaction.
Li2SrGeO4:RE3+ (RE = Tb/Dy/Ce) phosphors were prepared by the conventional solid-state reaction. X-ray diffraction (XRD), photoluminescence (PL) spectra, and lifetimes were utilized to characterize samples. Under the excitation of ultraviolet (231 nm for Tb3+ and 351 nm for Dy3+), the Li2SrGeO4:Tb3+ and Li2SrGeO4:Dy3+ phosphors show their respective characteristic emissions of Tb3+ (5D3,4 → 7FJ′, J′ = 3, 4, 5, 6) and Dy3+ (4F9/2 → 6H15/2 and 4F9/2 → 6H13/2), respectively. Ce3+ activated Li2SrGeO4 phosphors exhibit broad band blue emission due to the 5d–4f transition of Ce3+. Co-doping Ce3+ into the LSG: Ce3+/Dy3+ samples enhances the luminescence intensity of Tb3+ and Dy3+ significantly under the excitation wavelength at 340 nm through energy transfer from Ce3+ to Tb3+/Dy3+. In addition, the energy transfer mechanism between Ce3+ and Tb3+/Dy3+ has been demonstrated to be a resonant type via a dipole–quadrupole interaction.
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