Institut für Materialphysik

IMP-Seminar SoSe 2018

Unless noted otherwise, the IMP seminar commences at 16:00 (sharp) in our seminar room (SR11, C.03.101). Prior to the seminar (~15:40) coffee, tea, and cookies are being served in the same room.

Risch / Hoffmann-Urlaub / Volkert /Joos IMP Universität Göttingen
New Research Directions at IMP
Marcel Risch:
New DFG Project: Controlling Oxygen electrocatalysis on model oxide surfaces using electrolyte design
Sarah Hoffmann-Urlaub:
Perovskites & Halides
Cynthia Volkert:
IRTG Japan graduate School & Sino-German Research Project
Christian Joos:
EC-TEM plans
Kontakt: sekretariat @

--IMP Universität Göttingen
IMP student poster presentations
Kontakt: sekretariat @

to be announced
Kontakt: sekretariat @

Prof. Chun-Lin Jia Link: Xi’an Jiaotong University, China
Aberration-corrected transmission electron microscopy
The morphology and atomic details of interfaces in materials have significant influence on the physical, chemical and mechanical properties of materials. In particular, domain walls in ferroic oxides exhibit novel properties differing from the domain bulk. These novel properties have attracted considerable interest of research on the underlying physics with respect to strucural origin and their potential application in nano-electronics [1]. The successful development of modern aberration-corrected electron microscopes and various relevant techniques of imaging and analysis provide scientists great opportunities for accessing to studying, on a sub-angstrom scale, the structure and properties of interfaces. Moreover, advanced thin film technologies allow controlling and tailoring interfaces in film systems for tuning physical properties. In the presentation, we show examples for application of mordern aberration-corrected transmission electron microscopy to characterizing atomic details of domain walls in ferroic oxides. Employing the negative CS imaging (NCSI) technique [2] domain walls in thin films of ferroelectric Pb(ZrTi)O3 and in single crystal of multiferroic BiFeO3 are studied [3-5]. We measure with picometre precision the positions and relative displacements of the atoms in these materials. The precisely measured displacements of atoms are usued to determine the modulus and the direction of the electric dipole moments unit cell by unit cell and reavel the noval features oif domain walls and topological defects.
Kontakt: ltian @

to be announced
Kontakt: sekretariat @

24.05.2018 um 14:30 Uhr, Seminarraum SR11, C3.101
Prof.Dr. Reiner Kirchheim Institut für Materialphysik, Georg-August-Universität Göttingen
60 Jahre Materialwissenschaften
Kontakt: sekretariat @

30.05.2018 um 10:30 Uhr, Seminarraum SR11, C03.101
Emanuel Franke Institut für Materialphysik, Georg-August-Universität Göttingen
Untersuchungen der Wärmekapazität von Nanopartikeln und Multilagen mit der nanokalorimetrischen Methode
Kontakt: efranke @

31.05.2018 Sondertermin um 15:30 Uhr, Seminarraum SR11, C3.101
Prof. Astrid Pundt Institut für Materialphysik, Georg-August-Universität Göttingen
Kaffee und Kuchen mit Astrid!
Kontakt: sekretariat @

Jonas Arlt Institut für Materialphysik, Georg-August-Universität Göttingen
Analysis of Light Impurities by Means of Atom Probe Tomography
Kontakt: apundt @

Dr. Jørgen Schou Technical University of Denmark,
Pulsed laser deposition of chalcogenides for solar cells – the strongly non-stoichiometric material transfer
Mungunshagai Gansukh, Stela Canulescu and Jørgen Schou
DTU Fotonik, Technical University of Denmark, Risø Campus, DK-4000 Roskilde, Denmark
Films of chalcogenides are becoming increasingly important because of their role as absorbers in thin-film solar cells. These absorbers are typically sulfides, selenides or tellurides, of which CIGS (Cu(Ga,In)Se2) and CdTe have been studied comprehensively during the last thirty years. A new, promising, but less studied material is CZTS (Cu2ZnSnS4) which recently has reached a solar cell efficiency slightly above 10 %.
We have been inspired to produce films of quarternary sulfides by the success of pulsed laser deposition (PLD) for fabricating high-quality (stoichiometric) films of high-temperature superconductors for more than two decades.
However, films of CZTS have turned out to be difficult to produce by PLD, not only because the films should have a surplus of Zn relative to Cu to make good solar cells, but also because the mass transfer from target to films is incongruent in contrast to expectations of PLD as a stoichiometric film growth process. Films of CZTS and CTS (Cu2SnS3) have been produced by PLD at a fluence from 0.2 J/cm2 to 2 J/cm2 on room-temperature substrates with nanosecond lasers with wavelengths of 248 nm or 355 nm in vacuum. The resulting film composition was deficient in copper at low fluence and in sulfur in general for both chalcogenides [1]. The most surprising feature was a strong decrease in the copper content of the films with decreasing fluence. The results will be discussed on the basis of the thermodynamic properties of the materials [2].
[1] A. Cazzaniga, A. Crovetto, C. Yan, K. Sun, X. Hao, J. R. Estelrich, S. Canulescu, E. Stamate, N. Pryds, O. Hansen and J. Schou. Solar Energy Mat. and Solar Cells 166, 91–99 (2017)
[2] J. Schou, M. Gansukh, R. B. Ettlinger, A. Cazzaniga, M. Grossberg, M. Kauk-Kuusik and S. Canulescu. Appl. Phys. A 124, 78 (2018)
Kontakt: shoffmann

18.06.2018 Disputation um 10:00 Uhr, Seminarraum SR11, C03.101
Magnus Hamm Institut für Materialphysik, Georg-August-Universität Göttingen
Hydrogen diffusion and hydride formation in grain boundary rich magnesium
Kontakt: mhamm @

to be announced
Kontakt: sekretariat @

Dominik Tönnies Institut für Materialphysik, Georg-August-Universität Göttingen
"Early plasticity in metallic glasses"
Kontakt: Kontakt Tönnies

Achtung Seminar fällt aus / Failure of the seminar

Prof. Erwin Povoden-Karadeniz Computational Materials Engineering,TU Wien
Realisation of predictive defect chemistry evaluation of complex functional oxide materials for solar fuel production
Ceria-base fluorite and rare-earth perovskite are promising candidates for the production of synthetic H2+CO gas (syngas), in a two-step thermochemical cycle for H2O/CO2 splitting due to their high thermal stability and auspicious redox kinetics. In contrast to conventional fossil resources, syngas represents a renewable fuel. Both examined groups of metal oxides exhibit their specific strength for solar-to-fuel application: While Ceria shows extraordinary fast redox kinetics, it requires a high reduction temperature of at least 1500°C. On the other hand, oxygen release of rare earth perovskite of the La-Sr-Mn-O base system revealed high oxygen carrier capacity and lower required reduction temperatures. Further, in the essential CO-oxidation of H2 purification from syngas, CuO-doped Ceria represents a promising catalyst candidate with high activity. One concept for the optimisation of the solar-to-fuel process is increased efficiency by composition refinement of the chosen functional materials. For this purpose, predictive understanding of defect evolution and charge disproportionation reactions as function of temperature and oxygen partial pressure changes is necessary. A predictive concept of thermodynamic stabilities and defect chemistry evaluation of complex functional oxides, rare earth perovskite, and doped Ceria, based on optimized compound energies is presented. We apply an extension of a thermodynamic model for nonstoichiometric ionic solid solutions [1] and optimise thermodynamic model parameters by a wide variety of experimental data from calorimetry, thermogravimetry, differential thermal analysis, electric conductivity, and X-ray absorption spectroscopy. We provide consistent physical models of phase stabilities, thermodynamic state variables and related phase properties, including defect formation as function of temperature, oxygen partial pressure and solute doping concentrations. Oxygen deficiency of Ceria is reproduced by the model, which is adopted for a proper extension to the Ce-Cu-Oxide system. The evaluated defect chemistry of La-Sr-Mn-Cr-oxide perovskite is presented and discussed. Usability of our approach in solar fuel production technology is demonstrated by thermal efficiency calculations based on computational thermodynamic results obtained by the modeling [2]. Keywords: CuO-doped Ceria; perovskite; defect chemistry; modeling. 1. M. Hillert, L.-I.. Staffansson, A. Tiwari, Acta Chem. Scand., 1970, 24, 3618. 2. A.H. Bork, E. P
Homepage / Link: TU Wien
Kontakt: Kontakt Risch


Kontakt: Kontakt Sekretariat

IMP-Seminar WiSe 17/18

Unless noted otherwise, the IMP seminar commences at 16:00 (sharp) in our seminar room (SR11, C.03.101). Prior to the seminar (~15:40) coffee, tea, and cookies are being served in the same room.

15.09.2017 Friday, 11:15, C.03.101
Rouzbeh Abadi Institute of structural mechanics, Bauhaus University, Weimar, Germany
The effect of temperature and topological defects on fracture strength of grain
boundaries in single-layer polycrystalline boron-nitride nanosheet

Kontakt: rvink @

to be announced
Kontakt: sekretariat @

26.10.2017 Thursday, 16:00, C03.101
Benito Carlos Aramayo Facultad deHumanidades y Ciencias Sociales de la
Universidad Nacional de Jujuy, Argentina
Lithium mining in the Province of Jujuy and the environment
Kontakt: jooss @

02.11.2017um 17:00 im HS5 gemeinsame SFB 755 und SFB 1073 Veranstaltung
Prof.Gisela Schütz MPI für intelligente Systeme, Stuttgart
Scanning x-ray microscopy for chemical, magnetic, depth and temporal sensitivity
Kontakt: ckaspar @

09.11.2017 Thursday, 16:00, C03.101
Dr.Christine Borchers IMP Universität Göttingen
Nanocrystalline steels obtained by ball-milling of Fe and B, C, N, or
O: Similarities and discrepancies

Kontakt: cborche @

16.11.2017 Thursday, 16:00, C03.101
Max Steinbrück Institut für Materialphysik, Georg-August-Universität Göttingen
Design and Test of an In-Situ SEM Heating Sample Holder
In-Situ experimentation lives up to its full potential if transitions and transformations in specimen characteristics can be observed and documented time resolved during the change process. To witness those changes, like formation of voids and hillocks during electromigration in metals, elevated temperatures are often required to provide the necessary activation energy. For that, a heating sample holder for the Nano-SEM has been developed and built. In this talk, the possibilities and problems of sample heating in the Nano-SEM are presented and discussed.

Kontakt: msteinbrueck @

23.11.2017 Thursday 10:15 - 13:00, C03.101
Dr.Sarah Hoffmann-Urlaub Institut für Materialphysik, Georg-August-Universität Göttingen
safety instruction / Sicherheitsbelehrungen

to be announced
Kontakt: sekretariat @

Felix Rieger Institut für Materialphysik, Georg-August-Universität Göttingen
HRTEM studies and thermal conductivity measurements of epitaxially grown Sb2Te3 films
Thermoelectric materials are a very interesting topic of actual research due to their capability of converting heat into electricity without any moving parts and without the need of huge temperature gradients. A very promising and already used material is Sb2Te3. For further understanding the structure property relations in this material and optimizing its thermoelectric properties, epitaxial thin films have been synthesized by PVD and studied in the FEI TITAN ETEM. Thermal conductivity measurements have been made using the 3omega method. Furthermore, the Kapitza resistance of various involved interfaces has been determined, allowing for high precision determination of the film thermal conductivity. The analysis shows that the nearly single crystalline films show a remarkably small cross plane (c-axis) thermal conductivity pointing to an intrinsic limitation by the layered structure.

Kontakt: Sekretariat @

12.12.2017 Dienstag 9:00 Uhr in C03.101
-- Institut für Materialphysik
Mitgliederversammlung / Sicherheitsbelehrung
Kontakt: sekretariat @

Prof.Dr. Franz Faupel Chair for Multicomponent Materials, Faculty of Engineering, Kiel University
Functional Nanocomposites - From Fabrication to Function
Abstract Prof.Faupel als PDF
Kontakt: joss @

to be announced
Kontakt: sekretariat @

Dr.Christine Borchers IMP Universität Göttingen
Nanocrystalline steels obtained by ball-milling of Fe and B, C, N, or
O: Similarities and discrepancies

Kontakt: cborche @

18.01.2018 ..
Dr. Christoph Gammer, Erich Schmid Institute of Materials Science, Leoben, Austria
Local strain mapping during in situ deformation in the TEM
In situ TEM has provided great insight into the deformation mechanisms in various material systems. Advanced deformation holders in combination with well-defined sample geometries have enabled to obtain the stress-strain curve, but the local transient strain field during deformation remains unknown. In the present work we demonstrate local strain mapping during continuous in situ deformation in a TEM at the nanometer scale. This is achieved by scanning an electron beam over the sample and recording a full diffraction pattern for every probe position using a fast electron detector. The method is demonstrated for two different material systems, one being amorphous and the other one crystalline. In the first study, a CuZr-based metallic glass sample is deformed under tension. The ellipticity of the amorphous ring pattern can be used to map the local strain. In the second study an in situ tensile test of Al is shown. Here, cross correlation is used to detect the positions of the diffracted peaks, allowing to obtain time-resolved strain maps [1]. The strain maps demonstrate a large spread in local stresses associated with defects. 1. C. Gammer et al., Appl. Phys. Lett. 109 (2016) 081906.
Kontakt: ltian @

Herr Prof. Dr. Ralf Busch, Chair of Metallic Materials, Department of Materials Science and Engineering, Saarland University, Campus C63, 66123 Saarbrücken, Germany
Abstract Prof.Busch als PDF
Kontakt: sekretariat @

Moritz Roscher Institut für Materialphysik, Georg-August-Universität Göttingen
Herstellung und Charakterisierung von dünnen Eisen-Kohlenstoff Schichten für Elektromigrationsexperimente
Kontakt: mroscher @


to be announced
Kontakt: sekretariat @

IMP-Seminar SoSe 2017

Prof. Karl-Michael Weitzel, Philipps - Universität Marburg
Ionentransport in Festkörpern und dünnen Schichten - Elektrodiffusion, chemische Diffusion und Korngrenzendiffusion
Kontakt: jooss @

Prof. Dr. Astrid de Wijn, Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology NTNU, Trondheim Norwegen
Nanoscopic friction under electrochemical control
Kontakt: rvink @

22.05.2017 (Montag um 14:30 Uhr im Seminarraum SR11 C03.101)
Emanuel Franke, Universität Göttingen, Institut für Materialphysik
Save the DSC" -> Short presentation of DSC capabilities
Kontakt: volkert @


Prof. M. Zehetbauer, University of Vienna, Group Physics of Nanostructured Materials
H2 Speicherung in SPD prozessierten Nanomaterialien
Kontakt: chris @

02.06.2017 (Freitag um 10:00 Uhr im Seminarraum SR11 C03.101)
Dr. D. Setman, University of Vienna, Group Physics of Nanostructured Materials
Leerstellen- bzw. Fehlstellenhärtung mit H2 als Fehlstellen Trap
Kontakt: chris @

Mona Maaß, Universität Göttingen, Institut für Materialphysik
In-situ SEM / TEM fracture tests on (modified) tracheids of pine latewood
Kontakt: volkert @

To be announced

Magnus Hamm, Universität Göttingen, Institut für Materialphysik
Influence of grain boundaries on hydrogen diffusion in Magnesium
Kontakt: apundt @

Prof. Candace Chan, Materials Science & Engineering, Arizona State University, USA
Engineering Nanostructured Metal Oxides for Photocatalytic Applications
Kontakt: volkert @
Kontakt: mrisch @

Sarah Hoffmann-Urlaub, Universität Göttingen, Institut für Materialphysik
Physics of PLD
Kontakt: shoffmann @

To be announced