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Title: Expanding the synthetic toolbox to access pristine and rare-earth-doped BaFBr nanocrystals
A new synthetic route to access pristine and rare-earth-doped BaFBr nanocrystals is described. Central to this route is an organic–inorganic hybrid precursor of formula Ba 5 (CF 2 BrCOO) 10 (H 2 O) 7 that serves as a dual-halogen source. Thermolysis of this precursor in a mixture of high-boiling point organic solvents yields spherical BaFBr nanocrystals (≈20 nm in diameter). Yb:Er:BaFBr nanocuboids (≈26 nm in length) are obtained following the same route. Rare-earth-doped nanocrystals display NIR-to-visible photon upconversion under 980 nm excitation. The temperature-dependence of the green emission from Er 3+ may be exploited for optical temperature sensing between 150 and 450 K, achieving a sensitivity of 1.1 × 10 −2 K −1 and a mean calculated temperature of 300.9 ± 1.5 K at 300 K. The synthetic route presented herein not only enables access to unexplored upconverting materials but also, and more importantly, creates the opportunity to develop solution-processable photostimulable phosphors based on BaFBr.  more » « less
Award ID(s):
2003118
NSF-PAR ID:
10322034
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
50
Issue:
44
ISSN:
1477-9226
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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