Green upconversion luminescence and temperature sensitivity of LaOF:Yb,Ho phosphors

Nonaka, T.; Sugiura, T.; Tsukamoto, T.; Yamamoto, S. I.; Nonaka, T.; Sugiura, T.; Tsukamoto, T.; Yamamoto, S. I.

doi:2022.59.6.889

J. Korean Ceram. Soc. > Volume 59(6); 2022 > Article

Original Article

Journal of the Korean Ceramic Society 2022;59(6): 889-894.
doi: https://doi.org/10.1007/s43207-022-00231-y

Green upconversion luminescence and temperature sensitivity of LaOF:Yb,Ho phosphors

T. Nonaka¹

, T. Sugiura¹, T. Tsukamoto¹, S. I. Yamamoto²

¹Department of Electrical and Electronic Engineering, National Institute of Technology, Toyota College, 2-1 Eiseicho, Toyota, Aichi 471-8525, Japan
²Course of Electronics, Information and Communication Engineering, Faculty of Advanced Science and Technology, Ryukoku University, 1-5 Yokotani, Oe-cho, Seta, Ohtsu City, Shiga 520-2194, Japan

Correspondence

T. Nonaka ,Email: t-nonaka@toyota-ct.ac.jp

Received: March 2, 2022; Revised: June 11, 2022 Accepted: July 4, 2022. Published online: July 21, 2022.

ABSTRACT

The aim of this study is to synthesize green upconversion phosphors by introducing Yb and Ho into LaOF. Furthermore, we aim to use the obtained LaOF:Yb,Ho devices as temperature sensors. The results of the X-ray diff raction measurements showed that Tetragonal LaOF and Hexagonal LaF₃ were detected in the samples that were sintered for 1 h. The photoluminescence characteristics were analyzed under excitation at a wavelength of 980 nm, and a strong emission was observed at a wavelength of 543 nm (⁵F₄, ⁵S₂ → ⁵I₈). The temperature sensor was found to be stable. Furthermore, the sample showed a relative sensitivity of around 0.004 K⁻¹ regardless of the temperature.

Key words: LaOF · Yb · Ho · Upconversion · Thermometer