Terbium fluoride nanocrystals, covered by a shell, composed of cerium fluoride
were synthesized by a co-precipitation method. Their complex structure was
formed spontaneously during the synthesis. The surface of these core/shell
nanocrystals was additionally modified by silica. The properties of TbF3@CeF3
and TbF3@CeF3@SiO2 nanocrystals, formed in this way, were investigated.
Spectroscopic studies showed that the differences between these two groups of
products resulted from the presence of the SiO2 shell. X-ray diffraction
patterns confirmed the trigonal crystal structure of TbF3@CeF3 nanocrystals.
High resolution transmission electron microscopy in connection with energy-
dispersive X-ray spectroscopy showed a complex structure of the formed
nanocrystals. Crystallized as small discs, ‘the products’, with an average
diameter around 10 nm, showed an increase in the concentration of Tb3+ ions
from surface to the core of nanocrystals. In addition to photo-physical
analyses, cytotoxicity studies were performed on HSkMEC (Human Skin
Microvascular Endothelial Cells) and B16F0 mouse melanoma cancer cells. The
cytotoxicity of the nanomaterials was neutral for the investigated cells with
no toxic or antiproliferative effect in the cell cultures, either for normal
or for cancer cells. This fact makes the obtained nanocrystals good candidates
for biological applications and further modifications of the SiO2 shell