@article{bea71783625e4ec49a133f9786ac55e8,
title = "High temperature degradation mechanism of a red phosphor, CaAlSiN3:Eu for solid-state lighting",
abstract = "Thermal properties of a red phosphor CaAlSiN3:Eu (CASN) at elevated temperatures were evaluated. A heat treatment at 800 °C degraded the photoluminescence property of CASN and caused irreversible changes in both the excitation and emission intensities. The heat treatment in air simultaneously decreased the N elements and increased the O elements. Consequently, the Eu2+ luminescence center was oxidized and CASN lost its photoluminescence property. Although the crystal structure of CASN host was stable even after the heat treatments, the local structure change around the Eu2+ ions is the origin of the thermal degradation of CASN. We found that the heat treatment in N2 atmosphere suppresses the thermal degradation. This is due to the suppression of N evolutions and the incorporation of O elements, which sustains the optically active Eu2+ state.",
author = "Masatsugu Oishi and Shohei Shiomi and Takashi Yamamoto and Tomoyuki Ueki and Yoichiro Kai and Chichibu, {Shigefusa F.} and Aiko Takatori and Kazunobu Kojima",
note = "Funding Information: We thank Professor Daisuke Yonekura, Tokushima University, for the XPS experiments and Mr. Masashi Maeda, Tokushima University, for his help with the PL measurements. The authors appreciate Professor Toshihiro Moriga, Tokushima University, for his help with the diffuse reflectance measurements. We recognize Dr. Taigo Takaishi, Kyoto Municipal Institute of Industrial Technology and Culture, for the TG-MS measurements. The authors are grateful to and Dr. Fumito Fujishiro, Kochi University, for the fruitful discussions. This research was partially supported by a Grant-in-Aid for Challenging Exploratory Research (No. 15K14075) of the Japan Society for the Promotion of Science, and LIXIL JS Foundation. Publisher Copyright: {\textcopyright} 2017 Author(s).",
year = "2017",
month = sep,
day = "21",
doi = "10.1063/1.5003087",
language = "English",
volume = "122",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics",
number = "11",
}