Glass - Back to the Future!



Presenting Author:
Olga Dymshits
<vodym1959@gmail.com>

article posted 16 May 2016


Olga Dymshits is a Deputy Head of Glass Department (science) and a Head of Laboratory of Glass-ceramics at NITIOM Vavilov State Optical Institute, Saint Petersburg. She received her doctoral degree in Chemistry in 1991 from the Institute of Silicate Chemistry, Russian Academy of Science. Her scientific research interests include synthesis, characterization and investigation of structure and optical properties of amorphous and nanocrystalline materials, undoped as well as containing lanthanide and transition metal ions. Dr. Dymshits has published more than 90 scientific papers, she also holds many patents. She has received the Grebenschikov Medal for achievements in the field of optical materials science.






Rare earth niobates as luminescent nucleating agents in transparent glass-ceramics

I. Alekseeva1, O. Dymshits1*, M. Tsenter1, A. Vasilevskaya1, A. Zhilin1, V. Golubkov2, P. Loiko3, A. Malyarevich3, N. Skoptsov3, K. Yumashev3
1NITIOM Vavilov State Optical Institute, Babushkina 36/1, St. Petersburg, 192171, Russia
2Grebenshchikov Institute of Silicate Chemistry, St. Petersburg, Russia,
3Institute for Optical Materials and Technologies, Belarus National Technical University, Minsk, Belarus


Glass-ceramics with rare-earth ions embedded into crystalline phases are intensively studied due to the search for new efficient photoluminescent, up- and down-conversion multifunctional materials.
Combination of unique thermal-mechanical properties of lithium aluminosilicate glass-ceramics and their transparency with optical properties of rare-earth ions in oxide nanocrystals would allow developing new multifunctional materials.
Yttrium orthoniobate, YNbO4, is a self-activated X-ray phosphor widely used in X-ray medical imaging, in computed radiography, tomography and fluoroscopy. It is also an excellent luminescent host because yttrium ions are easily replaced by other rare-earth ions.
Glass-ceramics based on nanosized crystals of rare-earth niobates (where rare earth ion is Y, Yb, Er, Eu, Tm, Ho and their combination) with fluorite, tetragonal and monoclinic structure and β-quartz or β-spodumene ss were prepared in the LAS system [1].
Glass-ceramics comprised of rare-earth niobates with fluorite and tetragonal structure and β-quartz ss are transparent. Glass-ceramics loose transparency when rare-earth niobates with monoclinic structure and β-spodumene ss are crystallized.
Nanocrystals of rare earth niobates play a dual role of luminescent compounds and of nucleators of β-quartz ss. The spectral-luminescent properties of rare-earth ions are determined by the structure of the rare-earth niobate nanocrystals.
Rare-earth ions selectively enter the yttrium niobate crystals while transition metal ions selectively enter the lithium aluminosilicate crystals. The developed glass-ceramics are promising materials for lasers and phosphors.





Fig. 1. Images of the as-cast glass and glass-ceramics.










Fig. 2. XRD patterns of LAS glass-ceramics doped by Nb2O5 and Re2O3





References
1. O.S Dymshits, I.P. Alekseeva, A.A. Zhilin, M.Ya. Tsenter, P.A. Loiko, N.A.Skoptsov, A.M. Malyarevich, K.V. Yumashev, X. Mateos, A.V. Baranov, Structural characteristics and spectral properties of novel transparent lithium aluminosilicate glass-ceramics containing(Er,Yb)NbO4 nanocrystals J. Lumin. 160 (2015) 337345.

Acknowledgments
This work was partly supported by the RFBR (Grant 16-03-01130).