Single-Phase White-Emitting Phosphors Based on Apatite-Type Gadolinium Silicate, Gd9.33(SiO4)6O2 Doped with Dy3+, Eu3+ and Tb3+

Rodriguez-Garcia, Melissa Monzerrat; Williams, J.A. Gareth; Evans, Ivana Radosavljevic

Abstract

Two series of new apatite-type silicate materials were synthesised and characterised with the aim of achieving white light emission from single-phase phosphors. The Gd9.33(SiO4)6O2 host was doped systematically with Dy3+, Tb3+ and Eu3+ to tune the emission to the white light region. Eight new phosphors with emission very near the ideal white light point are reported. The best properties are found for the 0.5%Tb, 0.03%Eu co-doped Gd9.33(SiO4)6O2 , with colour coordinates (0.340, 0.341) and a correlated colour temperature of 5190 K, corresponding to the white light region. The temporal decay of emission from the doped ions was measured following pulsed excitation of the Gd3+ host. An evaluation of energy transfer and quenching effects in the phosphors has been made based on the lifetimes so obtained. In particular, a comparison of the Eu3+ lifetimes in the Dy,Eu co-doped phosphors with those in the Tb,Eu-containing materials suggests quenching of the 5D0 excited state of Eu3+ by the Dy3+ ions. These observations imply that the combination of Eu3+ and Dy3+ ions may not provide optimal efficiencies in phosphors, and that the combination of Eu3+ and Tb3+ is likely to be superior for optimising the emission properties.

Citation

Rodriguez-Garcia, M. M., Williams, J. G., & Evans, I. R. (2019). Single-Phase White-Emitting Phosphors Based on Apatite-Type Gadolinium Silicate, Gd9.33(SiO4)6O2 Doped with Dy3+, Eu3+ and Tb3+. Journal of Materials Chemistry C Materials for optical and electronic devices, 7(25), 7779-7787. https://doi.org/10.1039/c9tc02336d

• Journal Article Type: Article
• Acceptance Date: May 28, 2019
• Online Publication Date: May 29, 2019
• Publication Date: Jul 8, 2019
• Deposit Date: Jun 4, 2019
• Publicly Available Date: May 29, 2020
• Journal: Journal of Materials Chemistry C Materials for optical and electronic devices
• Print ISSN: 2050-7526
• Electronic ISSN: 2050-7534
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 25
• Pages: 7779-7787
• DOI: https://doi.org/10.1039/c9tc02336d
• Public URL: https://durham-repository.worktribe.com/output/1300592