학술논문
Determination of the refractive index of β-NaYF/Yb/Er/Tm nanocrystals using spectroscopic refractometry.
Document Type
Article
Author
Source
Subject
*Refractive index
*Nanocrystals
*Refractometers
*Near infrared spectroscopy
*Solution (Chemistry)
*Chemical synthesis
*Phosphors
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Language
ISSN
0030-400X
Abstract
A method for measuring refractive index n of nanosize particles in the visible and near-IR spectral ranges is proposed. The method is based on comparing refractive index n of a colloid solution of nanoparticles in several solvents with refractive indices n of corresponding pure solvents and has an accuracy of ±2 × 10. Upconversion nanosize phosphors (UCNPs) are synthesized in the form of a β-NaYF crystalline matrix doped with Yb, Er, and Tm rare earth ions. UCNPs have a doped core with a diameter of 40 ± 5 nm and undoped shell with a thickness of 3-5 nm. Synthesized nanocrystals possess intense photoluminescence in the blue, green, and red spectral ranges upon excitation by IR radiation with a wavelength of 977 nm. Using a spectroscopic refractometer, the dispersion of the refractive index of β-NaYF/Yb/Er/Tm nanocrystals was measured for the first time in the spectral range of 450-1000 nm with an accuracy of ±2 × 10. [ABSTRACT FROM AUTHOR]