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Wang, Dong; Wang, Minquan; Lu, Gaimin

doi:10.1023/a:1004759621850

Cited by 41 publications

(22 citation statements)

References 2 publications

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“…However, three of these are 4-fold coordinated by oxygen ions, and, as such, are not occupied by Mn 4+ ions, which exhibit the preference to enter the octahedral sites. The three remaining aluminum sites (the so called Al4, Al5, and Al6 sites 19 ) are in principle suitable for occupation by Mn 4+ . The crystal field calculations can aid a more precise identification of the impurity sites.…”

Section: Results and Discussion 31 Crystal Field Calculations Of Mn mentioning

confidence: 99%

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

et al. 2015

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Red phosphors play an indispensable role in phosphor-based warm white light emitting diodes (WLEDs). We demonstrated recently that the non-rare-earth phosphor Sr 4 Al 14 O 25 :Mn 4+ exhibits red luminescence even more intensely than the commercial Mn 4+ phosphor 3.5MgO.0.5MgF 2 .GeO 2 :Mn 4+ upon blue excitation. Herein, on the basis of crystal field calculations employing the exchange charge model, we identify the energy levels of three types of Mn 4+ ions situated at Al 3+ sites in the Sr 4 Al 14 O 25 crystal lattice and find that the doped manganese ions occupy preferentially the Al4 and Al5 more highly covalent sites rather than the Al6 site. We report that the Mn 4+ luminescence can be enhanced upon the inclusion of Mg 2+ in the synthesis reaction.The mechanisms for this effect comprise the lower nonradiative decay rate from the 2 E g state due to the reduction in energy migration along Mn 4+ ions to killer sites and also the morphology evolution from orderly layered smooth nanosheets to irregular nanoparticles disorderly compacted in porous bundles. Interestingly, various other phases are formed upon the addition of Mg 2+ . The resistance of Mn 4+ photoluminescence in the phosphor to thermal impact has also been studied and no obvious thermal degradation after a cycle experiment by heating and cooling the sample between 25 o C and 300 o C was found. As proof of concept, a warm perception WLED has been made when the phosphor was applied to the package of a blue LED chip and YAG:Ce.

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Section: Results and Discussion 31 Crystal Field Calculations Of Mn mentioning

confidence: 99%

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

et al. 2015

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“…The average Sr-O bond length for 10-fold coordinated strontium is equal to 2.77 Å and is longer than for the 7-fold coordinated strontium (2.62 Å). 37,41 The interactions between oxygen and strontium ions at the 10-fold coordinated site will be weaker than for the 7-fold coordinated site. A higher covalency and larger crystal field splitting are expected for Eu 2+ in the 7-fold coordinated site than in the 10-fold site due to the shorter Sr-O distances.…”

Section: Sr 4 Al 14 O 25 :Eu 2+mentioning

confidence: 99%

Eu²⁺luminescence in strontium aluminates

Dutczak

Jüstel

Ronda

et al. 2015

Phys. Chem. Chem. Phys.

153

107

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“…in flourescent lamps and plasma displays [1][2][3][4][5]. An important class of phosphors doped with Eu 2+ ions is based on alkaline earth aluminates [6]. In 1983, Van Kemenade and Hoeks reported that Sr4Al14O25:Eu 2+ ,Dy 3+ phosphor had a higher quantum efficiency and better long persistence properties than those of traditional aluminate and sulphide phosphors.…”

Section: Introductionmentioning

confidence: 99%

Synthesis, characterization and luminescence properties of long afterglow Phosphor Ba4Al14O25:Eu,Dy

2010

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Cited by 41 publications

References 2 publications

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

Eu²⁺luminescence in strontium aluminates

Synthesis, characterization and luminescence properties of long afterglow Phosphor Ba4Al14O25:Eu,Dy

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Untitled

Cited by 41 publications

References 2 publications

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn4+ Red Luminescence in Sr4Al14O25: Mn4+ for Warm WLEDs

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn4+ Red Luminescence in Sr4Al14O25: Mn4+ for Warm WLEDs

Eu2+luminescence in strontium aluminates

Synthesis, characterization and luminescence properties of long afterglow Phosphor Ba4Al14O25:Eu,Dy

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Product

Resources

About

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

Site Occupancy Preference, Enhancement Mechanism, and Thermal Resistance of Mn⁴⁺ Red Luminescence in Sr₄Al₁₄O₂₅: Mn⁴⁺ for Warm WLEDs

Eu²⁺luminescence in strontium aluminates