NaYF4 Microstructure, beyond Their Well-Shaped Morphology

Abstract

Lanthanide-doped nanoparticles are widely investigated for their optical properties. However, the sensitivity of the lanthanide ions’ luminescence to the local symmetry, useful when investigating structural environments, becomes a drawback for optimized properties in the case of poorly controlled crystallinity. In this paper, we focus on β-NaYF4 nanorods in order to provide a detailed description of their chemical composition and microstructure. The combination of detailed XRD analysis and TEM observations show that strong variation may be observed from particles from a same batch of synthesis, but also when considering small variations of synthesis conditions. Moreover, also the nanorods observed by SEM exhibit a very nice faceted shape, they are far from being monocrystalline and present significant local deviation of crystalline symmetry and orientation. All these structural considerations, sensitively probed by polarized emission analysis, are crucial to analyze for the development of optimal systems toward the targeted applications.

Impact of Excitation Intensity-Dependent Fluorescence Intensity Ratio of Upconversion Nanoparticles on Wide-Field Thermal Imaging

“…No cubic phase (α-phase) peak was found. Note that the β-phase NaYF 4 nanocrystals can produce higher UCF efficiency Figure b depicts the morphology of OA-UCNPs taken using transmission electron microscopy (TEM).…”

“…Note that the βphase NaYF 4 nanocrystals can produce higher UCF efficiency. 31 Figure 1b depicts the morphology of OA-UCNPs taken using transmission electron microscopy (TEM). The nanoparticles clearly have hexagonal shapes.…”

Peak Shift of Coherent Edge Radiation Spectrum Depending on Radio Frequency Field Phase of Accelerator

“…As it is difficult for the Voigt function to capture the outline of the distribution, a pseudo-Voigt function consisted of elementary functions is often used instead of the Voigt function in spectroscopy [27,28]. When the full width at half maximum of the Voigt function is defined as w v , S (z) can be approximated as the following equation [29,30]:…”

Compound-tunable embedding potential method: analysis of pseudopotentials for Yb in YbF2, YbF3, YbCl2 and YbCl3 crystals

“…Ytterbium fluoride, YbF 3 , is widely used in laboratory reagents, doping, laser materials, fluorite light-emitting materials, optical fibers, optical coating materials, and electronic materials. In particular, the Yb 3+ -doped oxyfluoride, 18 fluorophosphate 19 and other glasses, the NaYF 4 20,21 and LiYF 4 22 nanocrystals, which contain YbF 3 components, are unique materials with superior optical properties for a wide range of applications in photonics, luminescence, upconversion processes, etc. The heterostructures including the YbF 3 components play a significant role in development of dye-sensitized solar cells, 23,24 which are considered as materials for new generation photovoltaics.…”