Abstract
In this study the band gap and electronic structure of the next‐generation, red phosphor Sr[Mg3SiN4]:Eu2+ (SMS) are explored through a combination of soft X‐ray spectroscopy, density functional theory calculations, and thermal quenching data for the Eu2+ 5d→4f emissions. The results will be compared to those for the high‐efficiency phosphor Sr[LiAl3N4]:Eu2+ (SLA), which shows different, yet exceptional emission characteristics in the red‐spectral region. It is found that SMS has an indirect band gap of 3.28 ± 0.20 eV, strong uniformity in the density of states of its nonequivalent nitrogen sites, and an estimated energetic separation between the lowest Eu2+ 5d state and the conduction band of ≈0.13 eV. The Eu2+ 5d–conduction band separation in SLA is found to be ≈0.28 eV, which points to why the visible emissions of SLA, and not SMS, show outstanding thermal stability. A bonding scheme explaining the band gap difference of SMS and SLA is proposed based on the density of states of SMS. Modifications to each lattice are put forward for achieving optimized phosphor characteristics for use in pc‐LEDs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
