Publikationsdatum:
2019
Beschreibung:
The tunable color was obtained via the substitution of Sr2+, Ca2+, Zn2+ and Mg2+ ions for Ba2+ ions under the same excitation conditions. The emission color can be tuned from deep blue (0.15, 0.12) to cyan (0.16, 0.27) due to the variation of crystal field and distortion of the unit cell by replacing part of the host lattice cation Ba2+ with Sr2+, Ca2+, Zn2+ and Mg2+. The emission bands of BMBO:Ce3+, BZBO:Ce3+, BCBO:Ce3+ and BSBO:Ce3+ can be influenced by two factors: the crystal field splitting and centroid shifts.
Abstract
In this study, Sr2+, Ca2+, Zn2+, and Mg2+ ions act to tune the emission band to the blue‐cyan region in BaxSryB2O5:Ce3+ (BSBO), BaxCazB2O5:Ce3+ (BCBO), BaxZnuB2O5:Ce3+ (BZBO), and BaxMgvB2O5:Ce3+ (BMBO) phosphors. A red shift occurs with the increase of Sr2+, Ca2+, Zn2+, and Mg2+ concentration, and a blue shift occurs when the concentrations of Sr2+, Ca2+, Zn2+, and Mg2+ exceed the critical value. The emission color can be tuned from deep blue (0.15, 0.12) to cyan (0.16, 0.27) upon 365 nm UV lamp excitation due to the crystal field splitting and centroid shifts. The excitation band shift to long wavelength by introducing ions, so that the synthesized phosphor can be better matched with the n‐UV chip. The emission intensity slowly decreases with the temperature increasing. Therefore, the BMBO:Ce3+, BZBO:Ce3+, BCBO:Ce3+, and BSBO:Ce3+ phosphors with relatively good thermal stability were synthesized, which could have potential applications in the n‐UV white LEDs.
Print ISSN:
0002-7820
Digitale ISSN:
1551-2916
Thema:
Maschinenbau
,
Physik
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