Visible Discrimination of Broadband Infrared Light by Dye-Enhanced Upconversion in Lanthanide-Doped Nanocrystals

<div>HR-TEM images and relative upconversion efficiency illustrate the strong dependence on the reaction temperature for the properties of NaY<sub>0.747</sub>Yb<sub>0.25</sub>Tm<sub>0.003</sub>F<sub>4</sub> nanoparticles (a). At 300°C, small particles (12 nm or less) are formed with poorly defined crystal structure. At 315°C, Ostwald ripening results in large hexagonal phase particles with high lattice uniformity (b). In both images, the scale bar equals 20 nm. Under identical measurement conditions, the upconversion intensity for the 315°C-processed particles (black curve) is more than 10 times stronger than that from the 300°C-processed material (blue curve).</div>

Journal of Nanotechnology

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Figure 1

Figure 1: Visible Discrimination of Broadband Infrared Light by Dye-Enhanced Upconversion in Lanthanide-Doped Nanocrystals 