XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
200
T1: P–67
Influence of Gd
2
O
3
on spectroscopic properties
of aluminosilicate glasses
Marta Kasprzyk
1
, and Marcin Środa
1
1
AGH University of Science and Technology, Faculty of Materials Science and Ceramics, al.
Mickiewicza 30, 30-059 Kraków, Poland, e-mail: markas@agh.edu.pl
Optical active glasses must be accurately designed and thoroughly analyzed to achieve
desired luminescence properties. One of the way to enhance luminescence is to induce the
crystallization of low-phonon phase in the glass which can be a host for optical active elements,
for example, rear-earth elements. Low phonon energy of the crystallites ensure high
luminescence intensity and prolong lifetime due to higher share of radiative emission. For this
purpose the fluorides are used. The difficulty is that the crystallite phase has different ability to
accept optical active elements to its structure. Glass-ceramic materials with nanocrystalline, low
phonon phase are suitable for lasers, photonic devices for up- and down-conversion,
optoelectronic systems and also light amplifiers. Silicate glasses doped with LaF
3
[1], CaF
2
[2]
and BaF
2
[3] were studied. This work focuses on gadolinium, as this lanthanide has the ability to
form low-phonon phases with barium and fluoride (e.g. GdF
3
, BaGdF
5
) [4].
The aim of the research was to determine the influence of Gd
2
O
3
addition on spectroscopic
and optical properties of glasses from Na
2
O-BaO-Gd
2
O
3
-Al
2
O
3
-SiO
2
system. Five glasses with
Gd
2
O
3
content of 0, 2.5, 5, 7.5, 10 mol % were melted. Thermal analysis was carried out using
DSC method. On the basis of thermal analysis, controlled crystallization was conducted. The
glass-ceramic materials were identified by XRD. An impact of Gd
2
O
3
on spectroscopic and
optical properties was determined by analyzing FT-IR spectra, UV-VIS transmission and
refractive index.
Keywords: glass-ceramics; Gd
2
O
3
; GdF
3
; aluminosilicate glasses; spectroscopic properties
Acknowledgment
This work was supported by the statutory funds of AGH University of Science and Technology Faculty of
Materials Science and Ceramics No 11.11.160.365 in 2017.
References
[1] D Chen, Y Yu , P Huang, H Lin, Z Shan, Y Wang, Acta Mater. 58 (2010) 3035.
[2] S Georgescu, A Voiculescu, C Matei, C Secu, R Negrea, M Secu, J. Lumin. 143 (2013) 150.
[3] C Li, S Xu, R Ye, D Deng, Y Hua, S Zhao, S Zhuang, Physica B 406 (2011) 1698.
[4] M Kasprzyk, M Środa, M Szumera, J. Therm. Anal. Calorim. DOI: 10.1007/s10973-017-6354-9.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
201
T1: P–68
Spectroscopic study of glasses from TeO
2
-Ga
2
O
3
-GeO
2
system
Marcin Środa
1
, Agnieszka Marczewska
2
, Anna Szaniawska
1
Faculty of Material Science and Ceramics, AGH University of Science and Technology, A.
Mickiewicza 30, 30-059 Kraków, Poland
2
Institute of Ceramics and Building Materials, Division of Glass and Building Materials in Kraków,
Department of Glass Technology 30-702 Kraków, Lipowa 3, Poland, e-mail: a.marczewska@icimb.pl
Designing unconventional glasses for better properties is a fundamental step in engineering novel
devices for both near and mid-IR regions of the electromagnetic spectrum. Germanate based glasses
are of interest because of their excellent optical properties in the mid-IR region. These glasses
transmit to longer wavelengths when compared to borate, phosphate and silicate glasses because of
the heavier mass of germanium. Tellurium oxide and germanium oxide based glasses are classified as
the heavy metal oxide glasses, with phonon energies ranging between 740 and 880 cm
–1
. These two
types of glasses exhibit unique combinations of optical and spectroscopic properties, together with
their attractive environmental resistance and mechanical properties. The nonlinear optical properties
of tellurite and germanate glasses are an asset for generating short pulses, which is why it is important
to develop these glasses for 2 μm lasers.
The purpose of the research is to determine correlation between the glass structure and physic-
chemical properties as well as glass composition in the unexplored TeO
2
-Ga
2
O
3
-GeO
2
system. The
base tellurite-germanate glasses was modified by the addition of 10 mol% Ga
2
O
3
. The Ga
2
O
3
component plays the crucial role as glass stabilizer. The nominal molar composition of the glass was
(90–x)TeO
2
·10Ga
2
O
3
·xGeO
2
where x = 5, 20, 35, 55, 85 mol%.
The glasses are characterized by the transformation temperature (Tg) at the range of 346–374°C
and the onset temperature of crystallization above 400°C. The thermal stability of the glasses has been
reached greater than 60oC. It indicates the bulk glass can be easily fabricated. The glasses have poor
transmittance in the visible range but their transmittance in mid-IR up to 6 µm are high. We have
stated that more than 5% GeO
2
have significant impact on the increase of transmittance up to 60–75%
in the rage from 2.5 µm to 6 µm.
In the IR spectra of the 5TeO
2
·10Ga
2
O
3
·85GeO
2
glass broad bands in two regions, 850–920 and
520–580 cm
–1
, are presented (Fig. 1). Introduction of 5,
20, 35, 55 mol % GeO
2
results in appearing of the band
at 700 cm
–1
and vanishing of the band at 850–950 cm
–1
.
It was found that the more than one structural units
([TeO
4
] bi-pyramid, [TeO
3
] trigonal pyramid, and
[TeO
3
+δ] polyhedra) in tellurite and ([GeO
4
]
tetrahedron, [GeO
6
] octahedron) in GeO
2
based glasses
may exist, depending on composition (Fig. 1). The
germanium dioxide glass network resembles a silicate
network, with the exception that in this system not only
[GeO
4
] tetrahedrons form, but [GeO
6
] octahedrons can
also co-exist in some compositions, thereby offering
structural sites for dissolving octahedral 6-foldco-
ordinated structures. GeO
2
based glasses have an
extended visible-to-infrared transmission range from 2.5
µm to 6 µm, which makes these materials suitable for
mid-IR laser applications.
Keywords: tellurite-germanate glass; Ga
2
O
3
; UV-Vis; FT-IR spectroscopy; transmittance
Acknowledgments
This work was supported by the statutory funds of Institute of Ceramics and Building Materials Division of Glass
and Building Materials in Krakow, and AGH University of Science and Technology Department of Materials
Science and Ceramics AGH number WIMiC No 11.11.160.365 in 2017.
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