Temperature effect on fluorescence and UV–vis absorption spectroscopic properties of Dy(III) in molten LiCl–KCl eutectic salt

Optical absorption and fluorescence properties of trivalent lanthanide chlorides in high temperature molten LiCl–KCl eutectic

“…Recently, several groups have measured the fluorescence spectrum of Eu(II) in LiCl-KCl eutectic at various temperatures [38,61,69], whereas the fluorescence spectrum of Eu(III) has not been observed in high-temperature LiCl-KCl eutectic. The fluorescence properties of Eu(III), Eu(II), Tb(III), and Dy(III) were reported in our previous studies in detail [4,22,41].…”

“…In our previous study, the absorption spectrum of Dy(III) in the wavelength range from 200 nm to 1000 nm was obtained at 400°C, 500°C, and 600°C, and temperature-dependent molar absorptivity of the hypersensitive transition was analyzed [22]. Fig.…”

“…For that reason, a few experimental works have been performed by using spectroscopic techniques in the molten halide salts. The absorption spectroscopic properties of most lanthanides in various molten halide salts have been analyzed to investigate the structural symmetry of chemical constitution and redox behaviors and to determine their molar absorptivities for the purpose of quantification [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. However, the absorption spectra and the molar absorptivities in those literature works have not been completely reported for all lanthanide series.…”

“…Nevertheless, fluorescence spectroscopy has not yet been vigorously introduced in high temperature molten salt chemistry. The fluorescence spectra of a few lanthanides have been reported mostly at room temperature [38,39] and only recently, the fluorescence spectroscopic properties of Nd(III) [19], Tb(III) [4,40], Dy(III) [22], and Eu(III) [41] at elevated temperatures have been figured out. In this study, the systematic spectroscopic properties of all series of lanthanide elements (La, Ce, … , Yb, Lu), such as optical spectra of absorption and fluorescence, molar absorptivities, and fluorescence lifetimes, were explored in high temperature LiCl-KCl eutectic salt.…”

Structural investigation of the Tb(III)–Ln(III) (Ln=Nd, Sm) binary system in molten LiCl–KCl eutectic salt by fluorescence resonance energy transfer

“…However, it has not been actively applied for molten salt chemistry at high temperature. Recently, a few fluorescence spectroscopic measurements on single lanthanide element in molten chloride salts have been reported [32][33][34][35][36]. Nonetheless, there have not yet been adequate experimental evidences to prove chemical structure of a mixture of lanthanides in high temperature molten salts.…”