Synthesis of Core-Shell ScF3 Nanoparticles for Thermal Enhancement of Upconversion

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

65 Scopus Citations
View graph of relations

Detail(s)

Original languageEnglish
Pages (from-to)158–163
Journal / PublicationChemistry of Materials
Volume33
Issue number1
Online published15 Dec 2020
Publication statusPublished - 12 Jan 2021

Abstract

Lanthanide-doped ScF3 nanoparticles are synthesized and explored for thermal enhancement of upconversion. A hot-injection method is developed to control the formation of ScF3 nanoparticles with a core-shell nanostructure of uniform size and morphology. Temperature dependence of the upconversion emission is investigated in the temperature range from 168 to 308 K. In contrast to typical NaYF4:Yb/Er@NaYF4 nanoparticles that display thermally quenched emissions, a 3.7-fold enhancement of the upconversion emission is recorded for the ScF3:Yb/Er@ScF3 nanoparticles as the temperature is increased from 168 to 248 K because of the negative thermal expansion of the ScF3 host lattice. Besides, the emission profiles of the nanocrystals also display a strong temperature dependence, enabling convenient ratiometric thermometry with a relative sensitivity of 1.73%·K-1 at 168 K. As the core-shell nanoparticles are minimally susceptible to surface quenching, our findings may inspire new ideas for developing thermally enhanced upconversion nanoparticles with high emission intensities.