Cryogenic Luminescent Ratiometric Thermometers Based on Tetragonal Na[LnSiO(4)]center dot xNaOH (Ln = Gd, Tb, Eu; x approximate to 0.2)

authors	Ananias, D; Mongis, CM; Carlos, LD; Rocha, J
nationality	International
journal	EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
author keywords	Luminescent Thermometers; Lanthanides; Silicates; Temperature Sensing; Cryogenic
keywords	ORGANIC FRAMEWORK; LANTHANIDE SILICATE; TEMPERATURE; PHOSPHORS; EMISSION; NANOPARTICLES; EMITTERS; SPECTRA
abstract	The hydrothermal synthesis under mild conditions and structural characterization of Na[LnSiO(4)]center dot xNaOH (Ln = Gd, Tb, Eu; x approximate to 0.2) are reported. These materials crystallize in the tetragonal non-centrosymmetric I4(-) space group. The crystal phase purity is ascertained by powder X-ray diffraction and scanning electron microscopy, and further confirmed by photoluminescence spectroscopy and lifetime measurements at 294 and 12 K. Na[(Gd0.82Tb0.14Eu0.04)SiO4]center dot xNaOH and Na[(Gd0.66Tb0.30Eu0.04)SiO4]center dot xNaOH perform well as visible ratiometric thermometers, based on the ratio between the Tb3+ and Eu3+ emissions, presenting good relative thermal sensitivities at cryogenic temperature (<100 K) with maxima of 1.9 %K-1 at 14 K and 6.2 %K-1 at 12 K, respectively.
publisher	WILEY-V C H VERLAG GMBH
issn	1434-1948
isbn	1099-0682
year published	2020
volume	2020
issue	19
beginning page	1852
ending page	1859
digital object identifier (doi)	10.1002/ejic.202000057
web of science category	Chemistry, Inorganic & Nuclear
subject category	Chemistry
unique article identifier	WOS:000534207200005