Bright, Mechanosensitive Upconversion with Cubic-Phase Heteroepitaxial Core-Shell Nanoparticles.

ABSTRACT: Lanthanide-doped nanoparticles are an emerging class of optical sensors, exhibiting sharp emission peaks, high signal-to-noise ratio, photostability, and a ratiometric color response to stress. The same centrosymmetric crystal field environment that allows for high mechanosensitivity in the cubic-phase (α), however, contributes to low upconversion quantum yield (UCQY). In this work, we engineer brighter mechanosensitive upconverters using a core-shell geometry. Sub-25 nm α-NaYF₄:Yb,Er cores are shelled with an optically inert surface passivation layer of ∼4.5 nm thickness. Using different shell materials, including NaGdF₄, NaYF₄, and NaLuF₄, we study how compressive to tensile strain influences the nanoparticles' imaging and sensing properties. A

SUBMITTER: Lay A 

PROVIDER: S-EPMC6613353 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature