Nanothermometers
for local temperature measurements. (a) Schematics
(upper row) illustrating three different configurations for combining
nanoheaters and nanothermometers and transmission electron microscopy
(TEM) images (lower row) of representative hybrid nanostructures:
(1) (NaYF4:Yb,Er up-conversion nanoparticle (UCNP))@(mesoporous
silica (mSiO2))-(Au nanoparticle) core–satellite
nanoassemblies. Reprinted with permission from ref (394). Copyright 2019 Royal
Society of Chemistry. (2) (Au nanorod)-(NaGdF4:Yb,Er UCNP)
core–satellite nanoassemblies. Reprinted with permission from
ref (397). Copyright
2016 Wiley-VCH. (3) Polystyrene beads attached with Au nanostars and
CaF2:Nd3+,Y3+ UCNPs. Reprinted from
ref (400). Copyright
2019 Ivyspring International Publisher under the CC BY 4.0 license http://creativecommons.org/licenses/by/4.0/. (b) Illustrations showing temperature-sensing strategies relying
on (1) emission intensity, (2) peak position, (3) emission intensity
ratio, (4) emission lifetime, (5) fluorescence polarization anisotropy,
(6) electron spin resonance or ODMR. (c) Thermal sensitivities of
different luminescent nanothermometers and their spectral operation
ranges. Reprinted with permission from ref (391). Copyright 2017 Wiley-VCH.