공동침전법 기반 고발광 상향변환 나노입자의 합성법 및 특성 분석

초록

Lanthanide-doped upconversion nanoparticles (UCNPs) are capable of converting low energy near-infrared photons into relatively high energy visible and ultraviolet photon. Their unique optical properties have a broad range of applications such as volumetric display, security labelling and deep-tissue imaging. Herein, the optically active hexagonalphased NaYF4:Nd3+, Yb3+@NaYF4:Yb3+, Tm3+ core-shell nanoparticles were synthesized via facile co-precipitation method which can show upconversion luminescence upon 745 nm laser excitation. This is accomplished by taking advantages of the large absorption cross-section of Nd3+ ions between 720 to 760 nm plus efficient spatial energy transfer and migration which starts from Nd3+ ions to Yb3+ ions and Tm3+ ions. Also, the formation of inert NaYF4 shell significantly enhance the pconversion efficiency. The core-shell-shell UCNPs were characterized with X-ray diffraction (XRD) patterns, scanning electron microscope (SEM), transmission electron microscope (TEM), absorbance, and photoluminescence spectra.

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