Open Access27Al MAS NMR spectroscopy study of Eu2+-doped and Dy3+-co-doped SrAl4O7
Author(s) -
Martynas Misevičius,
Laurynas Dagys,
Arūnas Maršalka,
Kristina Kristinaitytė,
Vytautas Balevičius
Publication year - 2020
Publication title -
lithuanian journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.269
H-Index - 16
eISSN - 2424-3647
pISSN - 1648-8504
DOI - 10.3952/physics.v60i2.4224
Subject(s) - doping , analytical chemistry (journal) , amorphous solid , strontium , impurity , materials science , aluminate , spectroscopy , phase (matter) , nuclear chemistry , crystallography , chemistry , physics , optoelectronics , organic chemistry , chromatography , quantum mechanics , cement , metallurgy
The Eu 2+ -doped strontium aluminate SrAl 4 O 7 samples have shown the blue-green persistent luminescence at 490 nm while the co-doping with Dy 3+ shifts the maximum of emission to 475 nm. Undoped, 3% Eu-doped and 6% Dy-co-doped SrAl 4 O 7 samples were prepared by the solid state-reaction method and studied by the solid-state 27 Al MAS NMR applying the single pulse-acquire and Hahn-echo pulse sequences. It was shown that the Eu 2+ with Dy 3+ ion doping did not affect the bulk structure as well as the local Al environment in SrAl 4 O 7 . This means that large shifts of the emission maximum cannot be caused by changes in the local environment upon the co-doping of SrAl 4 O 7 :Eu 2+ with Dy 3+ . However, the spectral features observed in the range between the signals of 4- and 6-coordinated Al (20–40 ppm) indicate that certain phase imperfections are present in all studied samples, and most probably amorphous/glassy domains were formed. Note that such amount of phase impurities was not detected by standard XRD or FTIR methods. This has revealed the 27 Al MAS NMR technique to be a very effective tool monitoring the phase perfectness in series of strontium aluminate samples.