XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
174
T1: P–41
Influence of Ar-ion implantation on the structural properties of
zirconia as studied by Raman spectroscopy technique
Maciej Sitarz
1
, Lukasz Kurpaska
2
, Katarzyna Nowakowska-Langier
2
,
and Jaroslaw Jasinski
3
1
Faculty of Materials Science and Ceramics, AGH University of Science and Technology, av. A.
Mickiewicza 30, 30-059 Krakow, Poland
2
Material Physics Department, National Centre for Nuclear Research, st. Andrzeja Soltana 7, 05-400
Otwock-Swierk, Poland, e-mail: lukasz.kurpaska@ncbj.gov.pl
3
Institute of Materials Science, Czestochowa University of Science and Technology, av. Armii
Krajowej 19, 42-200, Czestochowa, Poland
Due to the good corrosion properties in the aggressive reactor environment and low thermal
neutron capture cross section, zirconium alloys are planned to be used as cladding materials in IV
generation nuclear reactors [1]. However, working temperatures of new generation nuclear reactors
vastly exceed today’s current designs. Therefore, studies of promising materials submitted to high
temperature conditions, which mimics working environment of the reactor is badly needed. One of
the biggest issues of current zirconium corrosion is the phase identification of high temperature
oxides and influence of radiative environment. Recent studies indicate that the oxide developed on
pure zirconium substrate consist of pure tetragonal and monoclinic phases [2] – so not, as many
believe mix of them [3]. Tetragonal phase is commonly believed to work as a protection against
corrosion and is stabilized until certain maximal stress level [4]. Therefore, by learning how to
stabilize the t-phase one may contribute to the future designs of the IV-gen reactors by improving
their efficiency and life time.
It is known that structural components working in the nuclear reactor are exposed to neutrons
which activates materials making them very difficult to study (dedicated Hot Cell Laboratory
equipped into highly specify equipment is needed). For this reason cost of the experiment is very
high. The solution to this problem is the ion implantation of the samples and post-mortem studies.
The impact of ion beam damages surface layer, changing local stress field, its structure and in
consequence, related mechanical properties. Structural properties of ion modified layers can be
studied by Raman spectroscopy technique. It has been proved that Raman band positions are sensitive
to the local stress field. Investigation of the ion irradiated layers by using Raman spectroscopy
technique can potentially provide data on which directions individual bands are shifted in the
damaged layer. Recorded shifts can additionally be a source of information on differences between
different phases in the damaged oxides. Presented work exhibits benefits from the use of Raman
spectroscopy in measuring structural properties of zirconia phases submitted to the ion damage.
In this study, the whole oxide scale have been analyzed by using Raman spectroscopy technique.
Cartographic images localized in the external part of the oxide, in the middle of the scale and on the
metal/oxide interphase have been presented. Reported results clearly shows: (i) existence of Raman
peaks characteristic for tetragonal phase located in the proximity of the zirconium substrate, (ii)
presence of monoclinic phase in the external part of the oxide and (iii) impact of Ar-ion damage on
the band positions. Presented work opens a new paradigm for future studies of high temperature
zirconium based oxides.
Keywords: zirconia; ion implantation; interface
Acknowledgment
Financial support from Ministry of Science and Higher Education through “Young Scientist” programme and
Foundation for Polish Science through “HOMING PLUS” programme is gratefully acknowledged.
References
[1] S.J. Zinkle, G.S. Was, Acta Mater. 61 (2013) 735.
[2] L. Kurpaska, J. Favergeon, L. Lahoche, M. El Marssi, J-L. Grosseau-Poussard, G. Moulin, J-M. Roelandt, J.
Nucl. Mater. 466 (2015) 460
[3] Y. Dali, M. Tupin, P. Bossis, M. Pijolat, Y. Wouters, F. Jomard, J. Nucl. Mater. 426 (2012) 148
[4] L. Kurpaska, I. Jozwik, J. Jagielski, J. Nucl. Mater. 476 (2016) 56.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
175
T1: P–42
Study of structural and spectral characteristics of simple polar
molecules under delamination of kaolinite
Georgy Lazorenko
1
, Anton Kasprzhitskii
1
, Victor Yavna
1
,
Yakov Ermolov
1
, and Kirill Ermolov
1
1
Department of Physics, Rostov State Transport University, Narodnogo Opolcheniya sq., 344038,
Rostov-on-Don, Russia, glazorenko@yandex.ru
Intercalation of clays, such as kaolinite, has been of considerable interest to develop
materials with different rheological, surface and structural properties. Kaolinite intercalation and
its application in polymer-based functional composites have attracted much attention, both in
industry and in academia. It is explained by the fact that these materials frequently demonstrate
remarkable improvements in desired properties as compared to the virgin polymer or
conventional micro and macro-composites [1]. A variety of inorganic and organic species can be
used for intercalation of interlayer spaces of kaolinite, including formamide, dimethylsulfoxide,
methanol, urea, potassium acetate, aniline, and hydrazine [2–5]. Intercalation of small molecules
into interlayer spaces of kaolinite can be used as a preliminary expansion step permitting
insertion of large-sized, non-reactive molecules by displacement intercalation methods.
Lately, some studies have been conducted with the use of molecular simulation method to
assess the intercalation of simple molecules in kaolinite [6]. Simulation is useful because it
allows a more detailed interpretation of experimental results, as well as it provides findings that
cannot easily be derived from strictly experimental data. In the majority of cases, experimental
observations alone cannot provide a clear picture of mechanism of molecular intercalation
process, or influences of intercalation on clay structure. On the other hand, quantum-chemical
simulations can contribute to gaining information about intercalation phenomena on microscopic
level. Despite previous studies exact organization and structure of molecular complexes in
interlayer space and on the edges of Kaolinite in the process of delamination demands further
studies. Nevertheless, application of DFT-simulation will enable to gain additional information
on the character of chemical bonds and structural organization of the complex “kaolinite - polar
molecule”.
The paper considers studies of delamination processes of kaolinite under its intercalation by
polar organic compounds. Structural and spectral characteristics of simple organic molecules
under their adsorption on basal surfaces and edges of kaolinite and in interlayer space have been
studied by DFT simulation methods. Types of adsorption centers and character of chemical
bonds in the system “kaolinite-polar molecule” have been stated. Allocated positions of polar
molecules determined by the peculiarities of basal surfaces of Kaolinite and presence of edge
faults have been disclosed. Besides, conditions under which process of delamination of kaolinite
have been established.
Keywords: kaolinite; DFT; delamination
Acknowledgment
This work is supported by the Grant of the President of Russian Federation No. 14.W01.17.2210-MK
of 22.02.2017
References
[1] Bergaya F., Lagaly G., Developments in Clay Science (2013) 707.
[2] Churchman G.J., Whitton J.S., Claridge G.G.C., et al., Clays and Clay Minerals (1984) 241.
[3] Costanzo P.M., Giese R.F.J., Clays and Clay Minerals (1986) 105.
[4] Komori Y., Enoto H., Takenawa R., et al., Langmuir (2000) 5506.
[5] Joussein E., Petit S., Delvaux B., Applied Clay Science (2007) 17.
[6] Benazzouz B.K., Zaoui A., Applied Clay Science (2012) 44.
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