Matthias Schwartzkopf

Dr. Matthias Schwartzkopf

orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 May 2012 in Journal of Synchrotron Radiation
Verified
Journal Article
Open access
PDF file
ABAdeline Buffet
Adeline Buffet
ARAndré Rothkirch
André Rothkirch
RDRalph Döhrmann
Ralph Döhrmann
VKVolker Körstgens
Volker Körstgens
MKMottakin M. Abul Kashem
Mottakin M. Abul Kashem
SRStephan V. Roth
Stephan V. Roth
The P03 beamline, also called the microfocus and nanofocus X-ray scattering (MiNaXS) beamline, exploits the excellent photon beam properties of the low-emittance source PETRA III to provide a microfocused/nanofocused beam with ultra-high intensity for time-resolved X-ray scattering experiments. The beamline has been designed to perform X-ray scattering in both transmission and reflection geometries. The microfocus endstation started user operation in May 2011. An overview of the beamline status and of some representative results highlighting the performance of the microfocus endstation at MiNaXS are given.

30 September 2014 in Journal of Applied Crystallography
Verified
Journal Article
Open access
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GBGunthard Benecke
Gunthard Benecke
WWWolfgang Wagermaier
Wolfgang Wagermaier
CLChenghao Li
Chenghao Li
MSMatthias Schwartzkopf
Matthias Schwartzkopf
GFGero Flucke
Gero Flucke
Peter FratzlPeter Fratzl
Peter Fratzl
X-ray scattering experiments at synchrotron sources are characterized by large and constantly increasing amounts of data. The great number of files generated during a synchrotron experiment is often a limiting factor in the analysis of the data, since appropriate software is rarely available to perform fast and tailored data processing. Furthermore, it is often necessary to perform online data reduction and analysis during the experiment in order to interactively optimize experimental design. This article presents an open-source software package developed to process large amounts of data from synchrotron scattering experiments. These data reduction processes involve calibration and correction of raw data, one- or two-dimensional integration, as well as fitting and further analysis of the data, including the extraction of certain parameters. The software,DPDAK(directly programmable data analysis kit), is based on a plug-in structure and allows individual extension in accordance with the requirements of the user. The article demonstrates the use ofDPDAKfor on- and offline analysis of scanning small-angle X-ray scattering (SAXS) data on biological samples and microfluidic systems, as well as for a comprehensive analysis of grazing-incidence SAXS data. In addition to a comparison with existing software packages, the structure ofDPDAKand the possibilities and limitations are discussed.

8 April 2013 in Nanoscale
Verified
Journal Article
Closed access
PDF file
MSMatthias Schwartzkopf
Matthias Schwartzkopf
ABAdeline Buffet
Adeline Buffet
VKVolker Körstgens
Volker Körstgens
EMEzzeldin Metwalli
Ezzeldin Metwalli
KSKai Schlage
Kai Schlage
SRStephan V. Roth
Stephan V. Roth
The adjustment of size-dependent catalytic, electrical and optical properties of gold cluster assemblies is a very significant issue in modern applied nanotechnology. We present a real-time investigation of the growth kinetics of gold nanostructures from small nuclei to a complete gold layer during magnetron sputter deposition with high time resolution by means of in situ microbeam grazing incidence small-angle X-ray scattering (μGISAXS). We specify the four-stage growth including their thresholds with sub-monolayer resolution and identify phase transitions monitored in Yoneda intensity as a material-specific characteristic. An innovative and flexible geometrical model enables the extraction of morphological real space parameters, such as cluster size and shape, correlation distance, layer porosity and surface coverage, directly from reciprocal space scattering data. This approach enables a large variety of future investigations of the influence of different process parameters on the thin metal film morphology. Furthermore, our study allows for deducing the wetting behavior of gold cluster films on solid substrates and provides a better understanding of the growth kinetics in general, which is essential for optimization of manufacturing parameters, saving energy and resources.

1 June 2015 in ACS Applied Materials & Interfaces
Verified
Journal Article
Open access
MSMatthias Schwartzkopf
Matthias Schwartzkopf
GSGonzalo Santoro
Gonzalo Santoro
CBCalvin J. Brett
Calvin J. Brett
ARAndré Rothkirch
André Rothkirch
OPOleksandr Polonskyi
Oleksandr Polonskyi
SRStephan V. Roth
Stephan V. Roth
The reproducible low-cost fabrication of functional metal–polymer nanocomposites with tailored optoelectronic properties for advanced applications remains a major challenge in applied nanotechnology. To obtain full control over the nanostructural evolution at the metal–polymer interface and its impact on optoelectronic properties, we employed combined in situ time-resolved microfocus grazing incidence small angle X-ray scattering (μGISAXS) with in situ UV/vis specular reflectance spectroscopy (SRS) during sputter deposition of gold on thin polystyrene films. On the basis of the temporal evolution of the key scattering features in the real-time μGISAXS experiment, we directly observed four different growth regimes: nucleation, isolated island growth, growth of larger aggregates via partial coalescence, and continuous layer growth. Moreover, their individual thresholds were identified with subnanometer resolution and correlated to the changes in optical properties. During sputter deposition, a change in optical reflectivity of the pristine gray-blue PS film was observed ranging from dark blue color due to the presence of isolated nanoclusters at the interface to bright red color from larger Au aggregates. We used simplified geometrical assumptions to model the evolution of average real space parameters (distance, size, density, contact angle) in excellent agreement with the qualitative observation of key scattering features. A decrease of contact angles was observed during the island-to-percolation transition and confirmed by simulations. Furthermore, a surface diffusion coefficient according to the kinetic freezing model and interfacial energy of Au on PS at room temperature were calculated based on a real-time experiment. The morphological characterization is complemented by X-ray reflectivity, optical, and electron microscopy. Our study permits a better understanding of the growth kinetics of gold clusters and their self-organization into complex nanostructures on polymer substrates. It opens up the opportunity to improve nanofabrication and tailoring of metal–polymer nanostructures for optoelectronic applications, organic photovoltaics, and plasmonic-enhanced technologies.

16 June 2014 in Applied Physics Letters
Verified
Journal Article
Closed access
GSG. Santoro
G. Santoro
SYS. Yu
S. Yu
MSMatthias Schwartzkopf
Matthias Schwartzkopf
PZP. Zhang
P. Zhang
Sarathlal Koyiloth VayalilSarathlal Koyiloth Vayalil
Sarathlal Koyiloth Vayalil
SRS. V. Roth
S. V. Roth
The fabrication of substrates for Surface Enhanced Raman Scattering (SERS) applications matching the needs for high sensitive and reproducible sensors remains a major scientific and technological issue. We correlate the morphological parameters of silver (Ag) nanostructured thin films prepared by sputter deposition on flat silicon (Si) substrates with their SERS activity. A maximum enhancement of the SERS signal has been found at the Ag percolation threshold, leading to the detection of thiophenol, a non-resonant Raman probe, at concentrations as low as 10−10M, which corresponds to enhancement factors higher than 7 orders of magnitude. To gain full control over the developed nanostructure, we employed the combination of in-situ time-resolved microfocus Grazing Incidence Small Angle X-ray Scattering with sputter deposition. This enables to achieve a deepened understanding of the different growth regimes of Ag. Thereby an improved tailoring of the thin film nanostructure for SERS applications can be realized.

14 January 2021 in ACS Sustainable Chemistry & Engineering
Verified
Journal Article
Closed access
IRIuliana Ribca
Iuliana Ribca
MJMarcus E. Jawerth
Marcus E. Jawerth
CBCalvin J. Brett
Calvin J. Brett
MLMartin Lawoko
Martin Lawoko
MSMatthias Schwartzkopf
Matthias Schwartzkopf
MJMats Johansson
Mats Johansson