کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1460835 | 989610 | 2015 | 6 صفحه PDF | دانلود رایگان |
Ce3+-doped and Ce3+–Tb3+ co-doped Na0.34Ca0.66Al1.66Si2.34O8 (NCASO) phosphors have been synthesized via a high temperature solid-state reaction method. The samples were measured by using X-ray diffraction (XRD), photoluminescence (PL) and photoluminescence excitation (PLE) spectra. The results of XRD indicated that the as-prepared samples were pure NCASO phosphors. The Ce3+-doped NCASO phosphor exhibited an intense blue emission centered at 414 nm under 335 nm excitation. The optimal doping concentration of Ce3+ in NCASO was confirmed 0.75 mol%. The concentration quenching occurs beyond 0.75 mol% of Ce3+ because of electric quadrupole–quadrupole interaction between Ce3+ ions. To tune the luminescent color of NCASO:Ce3+ phosphor, Tb3+ ions were introduced into the lattice of NCASO:Ce3+ phosphor. It was found the emission intensity of Ce3+ ions decreases gradually with the increase of Tb3+ ions concentration owing to energy transfer from Ce3+ to Tb3+. Moreover, the emitting colors can be adjusting from blue to green. The electric dipole–dipole interaction was induced to be responsible for energy transfer between Ce3+ to Tb3+. These results show that NCASO:Ce3+, Tb3+ phosphors can be used as a potential single-phased white-emitting candidate for UV WLEDs.
Journal: Ceramics International - Volume 41, Issue 1, Part B, January 2015, Pages 1341–1346