https://scholars.lib.ntu.edu.tw/handle/123456789/576252
標題: | Synthesis and design of NaYF4 microprisms via a microwave-assisted approach for highly sensitive optical thermometry applications | 作者: | Som S Lu C.-H Yang C.-Y Das S. CHUNG-HSIN LU |
關鍵字: | Boltzmann equation; Chelation; Crystallization; FIR filters; Irradiation; Microwave irradiation; Nucleation; Boltzmann distribution; Green fluorescence; Laser-induced heating; Microwave assisted; Microwave-assisted hydrothermal; Nucleation process; Optical thermometry; Precursor solutions; Sodium compounds | 公開日期: | 2021 | 來源出版物: | Journal of the American Ceramic Society | 摘要: | Hexagonal NaYF4: Er3+/Yb3+?(β-NaYF4) microprisms with uniform particle sizes were synthesized via a microwave-assisted hydrothermal method (MWHM). Nucleation and crystal growth were significantly surpassed owing to the microwave irradiation. Cubic-NaYF4: Er3+/Yb3+ (α-NaYF4) nanoparticles were transformed into?β-NaYF4 microprisms with reaction time in between 10 and 120?minutes at 180°C. The shape of the particles was enhanced via controlling the nucleation process with optimized irradiation duration and heating rates. The size distribution of β-NaYF4 microprisms was further improved via regulating the concentration of chelating agents and pH values in the precursor solution. β-NaYF4 microprisms displayed red and green color emissions for 980?nm excitation owing to the 4F9/2 and 2H11/2/4S3/2?→?4I15/2?transitions of Er3+ respectively.?The ratio (2H11/2/4S3/2?→?4I15/2) between green fluorescence intensities (FIR) of?β-NaYF4 microprisms was recorded?with the variation in temperature from?303?K to 550?K. The recorded FIR values obeyed Boltzmann distribution and the distribution was used to evaluate the sensitivity. The optimum absolute sensitivity was achieved as 0.0044?K?1?at 490?K with promising resolution, reversibility, and stability. Furthermore, the power-dependent variations in?FIR values?implied the suitability of?β-NaYF4 microprisms in measuring the laser-induced heating effects. ? 2021 American Ceramic Society |
URI: | https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103368173&doi=10.1111%2fjace.17783&partnerID=40&md5=02ffaa218194563937fe9f870a21a217 https://scholars.lib.ntu.edu.tw/handle/123456789/576252 |
ISSN: | 27820 | DOI: | 10.1111/jace.17783 |
顯示於: | 化學工程學系 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。