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Updated: Nov 14, 2025
Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications
Published on: November 10, 2017
Deciphering the role of temperature in Li+ co-dopant occupancy in BaYF5:Yb3+,Er3+ up-converting nanocrystals and its
Suman Devi1, Meitram Niraj Luwang1
1Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Pune 411008, India.
Abstract:
Precision engineering of defects in luminescent nanoscale crystalline materials with lesser controls to design is an area of interest in engineering materials with desired properties. Li+ co-doped BaYF5 nanocrystals were engineered, and temperature as controls for determining the co-dopant occupancies in the host lattice is studied. An observed enhancement in the up-conversion photoluminescence results from the co-dopant occupancy at Ba2+ sites via substitution through the hot injection method, whereas for samples prepared using co-precipitation, photoluminescence quenching was observed, which can be correlated with the Li+ occupancy at the interstitial site near Er3+ and also due to the incorporation of OH-. The crystal lattice deformation as a result of doping and the mechanism for the observed enhancement/quenching of luminescence are studied using x-ray diffraction, x-ray photoelectron spectroscopy, and energy transfer mechanism. Cytotoxicity assay and photoluminescence studies of the synthesized nanocrystals confirm that the material is biocompatible.
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