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Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications
Published on: November 10, 2017
Artificial Atomic Vacancies Tailor Near-Infrared II Excited Multiplexing Upconversion in Core-Shell Lanthanide
Jinzhao Huang1, Jingqiu Li2, Xuefei Zhang1
1National Research Centre for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Abstract:
Epitaxial growth of an inert shell around the optical active lanthanide upconversion nanoparticles (UCNPs) is a general strategy to enhance their brightness. Yet, its potential as a tool in multiplexing emission tailoring has rarely been reported. Here, by developing the atomic vacancies into color selectivity actuators, we present an efficient strategy to achieve inert-shell-modulated multiplexing upconversion in 1540 nm activated UCNPs. Artificially generated fluoride atomic vacancies, owing to the decreased NaOH/NH4F dosage during shell growth, reduce the coordination number of Y-F and lattice densities in the inert shell, leading to the core-engineered shell nanoparticles with distinctive emission profiles. The multicolor tailoring is independent of shell thickness and can be readily applied to Lu3+/Gd3+-based shells. The upconversion emission can be exploited to visualize in security decoding and in vivo multiplexing bioimaging. This method of regulating atomic vacancies based on the inert-shell engineering opens new insights of upconversion modulation in core-shell lanthanide nanostructures.
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