Thomas Gigl
16/06/2015, 12:20
Material Science
Short talk
The positron beam facility NEPOMUC at the FRM II provides a mono-energetic positron beam with an intensity of 10^9 moderated e+/s. The CDB spectrometer at NEPOMUC enables depth dependent and spatially resolved defect studies by using conventional doppler broadening spectroscopy(DBS), and element-specific measurements with coincident DBS. For depth dependent measurements, the positron...
Neelima Paul
18/06/2015, 10:06
Material Science
Short talk
Titania nanotube arrays are an interesting alternative anode material for use in Li-ion batteries due to their excellent cycling stability and enhanced safety compared to graphite. Moreover when such nanotube arrays are used as support for a thin silicon film, the resulting composite material has the additional advantage of a high lithium storage capacity. We present a detailed comparison of...
Luca Silvi
18/06/2015, 09:00
Material Science
Short talk
Among the complex hydrides, magnesium borohydride is attractive due to a quite good thermodynamic stability and high hydrogen storage capacity (14.9 H2 wt %). Quasielastic neutron scattering (QENS) has been performed beta phase of Mg(11BH4)2 at the cold neutron time-of-flight spectrometer TOFTOF at FRM II, Munich. Spectra were reordered in the range of temperature from 11 to 500 K, in order to...
Stefan Seidlmayer
16/06/2015, 12:00
Material Science
Short talk
We report on our measurements with the SANS-1 instrument at Heinz Maier-Leibnitz Zentrum (MLZ), Garching. In-operando small-angle neutron scattering data of NMC||Separator||Graphite cells was collected during a complete charging and discharging cycle. In addition single battery components were measured separately to distinguish the various component signals.
The in-operando data shows a...
Zsolt Revay
16/06/2015, 11:40
Material Science
Short talk
Prompt gamma activation analysis (PGAA) at MLZ has been successfully applied for the analyses of a large variety of samples even with masses less than a milligram, as well as for the investigation of low-cross-section nuclides and radioactive targets. Recently, a low-background counting chamber has been installed next to the PGAA instrument thus enabling the counting of induced radioactivity....
Dr
Wolfgang Kreuzpaintner
(Technische Universität München, Physik-Dep. E21)
18/06/2015, 09:44
Material Science
Short talk
While the structural characterisation of thin films during growth by various in-situ techniques is common practice, the in-situ measurement of the magnetic properties of films using (polarized) neutron reflectometry is a challenging task. Within a collaboration of TUM, Uni Augsburg and MPI Stuttgart, we operate a mobile sputtering facility for the growth and in-situ monitoring of magnetic...
Samantha Zimnik
16/06/2015, 11:20
Material Science
Short talk
The characterization of the elemental composition of surfaces is of high importance for the understanding of many surface-related processes such as catalysis or oxidation.
Positron annihilation induced Auger Electron Spectroscopy (PAES) is a powerful technique to gather information about the elemental omposition of only the topmost atomic layer of a specimen. The positron beam facility...
Christoph Hugenschmidt
(TUM)
16/06/2015, 11:00
Material Science
Short talk
In solid state physics and surface science the positron is applied as a highly mobile nano-probe for the detection of vacancy-like defects and their chemical surrounding in a non-destructive way. Positron lifetime measurements with pulsed beams allow the identification of different types of vacancies. Benefitting from the elemental sensitivity and selectivity of the positron, buried metallic...
Lukas Karge
18/06/2015, 09:22
Material Science
Short talk
Co-Re alloys are being developed in order to supplement Ni-base superalloys in future gas turbines for ultra-high temperature applications. The complex interplay between the different existing mesoscopic phases could be studied in-situ at high temperatures. It was shown that the amount and distribution of the stabilizing mono-carbide of TaC phase strongly depends on the stoichiometry of...