Hydrogen-containing Na3HTi1–xMnxF8 narrow-band phosphor for light-emitting diodes

We synthesize the phosphor Na3HTi1–xMnxF8 (Na3HTiF8:Mn4+) material series using a coprecipitation method. We determine the complete phase and crystallographic structure of the Na3HTiF8 series end-member, including the determination of the H atoms at the 4b (0, 1/2, 0) crystallographic site within the Cmcm space group symmetry structure, resulting in a quantum efficiency of ∼44%, which is comparative to the Na2SiF6:Mn4+ phosphor materials. We successfully model the luminescent properties of the Na3HTi1–xMnxF8 material series, including temperature and time-dependent photoluminescence, providing a good prediction of the decay properties at low and high temperature and revealing the existence of Mn5+ during the ionization process. Notably, LED package data indicates that the Na3HTi1–xMnxF8 material series could be a promising candidate for high-level and back-lighting devices. This research reveals the role that hydrogen plays in determining fluoride phosphor structure and properties, revealing a new path for the synthesis of fluoride phosphors. Copyright © 2019 American Chemical Society

Keywords

Materials, Hydrogen, Phosphors, Light-emitting diodes, Luminescence, Anions, Transition elements

Citation

Fang, M.-H., Yang, T.-H., Lesniewski, T., Lee, C., Mahlik, S., Grinberg, M., Peterson, V. K., Didier, C., Pang, W. K., Su, C. & Liu, R.-S. (2019). Hydrogen-containing Na3HTi1–x Mn x F8 narrow-band phosphor for light-emitting diodes. ACS Energy Letters, 4(2), 527-533. doi:10.1021/acsenergylett.8b02307