Abstract
The suite of LED phosphors M2Si5N8:Eu2+ (M = Ca, Sr, Ba) emerged as indispensable solid-state light sources for the next-generation lighting industry and display systems due to their unique properties. As such, the structure-property relations underpinning their electronic structures are of prime interest. Their band gaps, electronic structures, optical properties, and energy levels are studied with a combination of soft X-ray spectroscopy and density functional theory (DFT) calculations. A clear trend is found where the tunable band gaps range from 3.70 +/- 0.20 to 5.00 +/- 0.20 eV (when going from Ba to Sr to Ca), following the predictions of the bonding model. The measurements and calculations are also used to derive a systematic trend between the measured band gaps of M2Si5N8 and are confirmed by our density functional theory calculations employing different exchange correlation functionals. These investigations present a comprehensive picture of the M2Si5N8 system, underlining their broad applicability and importance as one of the preeminent phosphors for LED lighting.
Item Type: | Journal article |
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Faculties: | Chemistry and Pharmacy > Department of Chemistry |
Subjects: | 500 Science > 540 Chemistry |
ISSN: | 1932-7447 |
Language: | English |
Item ID: | 102602 |
Date Deposited: | 05. Jun 2023, 15:40 |
Last Modified: | 05. Jun 2023, 15:40 |