12 March 2019
Additive manufacturing of high-entropy alloys combines the mechanical properties of this
novel family of alloys with the geometrical freedom and complexity required by modern
designs. An approach to additive manufacturing of high-entropy alloys has been
developed based on 3D extrusion of inks containing a blend of oxide nanopowders (Co3
+ NiO), followed by co-reduction to metals, inter-diffusion and sintering to
near-full density CoCrFeNi in H2
. A complex phase evolution path is observed by in-situ X-ray
diffraction in extruded filaments: the oxide phases undergo reduction and the resulting
metals inter-diffuse, ultimately forming the desired fcc-CoCrFeNi alloy (see figure).
Linked to this phase evolution is a complex micro-structural one, from loosely packed oxide
particles to fully-annealed, metallic CoCrFeNi with 99.6 ± 0.1% relative
density. CoCrFeNi micro-lattices are created with strut diameters as low as 100 μm and
excellent mechanical properties at ambient and cryogenic temperatures.
6 March 2019
Abdominal aortic aneurysm, an enlargement of the abdominal aorta, may lead to rupture and thus acute health issues and death.
Scanning X-ray imaging enabled new insights in the nano-structure of calcifications associated with abdonimal and popliteal aneurysm and allowed mapping the distribution of nano- and micro-calcifications as well as of collagen, elastin and myofilament as building blocks of connective tissue across samples from human donors.
1 February 2019
Media Releases Matter and Material Research Using Synchrotron Light
A method developed by PSI researchers makes X-ray images of materials even better. The researchers took a number of individual images while moving an optical lens. From these, with the help of computer algorithms, they generated one overall image.
16 October 2018
The reliable electrical detection of magnetic skyrmions is of fundamental importance for the application of such topological magnetic quasi-particles for data storage devices. Researchers in a joint collaboration between the University of Leeds and the PolLux endstation have investigated the electrical detection of isolated magnetic skyrmions in applications-relevant nanostructured devices, observing the presence of a strong skyrmion-dependent contribution to the Hall resistivity.
11 July 2018
Media Releases Research Using Synchrotron Light Large Research Facilities Materials Research Matter and Material
The electronics industry expects a novel high-performance transistor made of gallium nitride to offer considerable advantages over present-day high-frequency transistors. Yet many fundamental properties of the material remain unknown. Now, for the first time, researchers at the Paul Scherrer Institute PSI have observed electrons while they were flowing in this promising transistor. For that they used one of the world's best sources of soft X-rays at PSI's Swiss Light Source SLS.
20 June 2018
In March 2018, the nine-week MOOC “Introduction to synchrotrons and x-ray free-electron lasers” (abbreviated to “SYNCHROTRONx”) came online via the edX provider of the École Polytechnique Fédérale de Lausanne (EPFL), created by Phil Willmott of the Swiss Light Source, Paul Scherrer Institute. “MOOC” is an acronym for “massive open online course”, a teaching platform started in the first decade of this century, which has become increasingly popular in the last five to six years. MOOCs have no limits to participation and are free. Some of the most popular MOOCs can attract many tens of thousands of participants. Even the most specialized subjects may have an initial enrollment of over a thousand, more than an order of magnitude larger than that typically found in traditional higher education. There were over 70 million MOOC enrollments covering nearly 10’000 subjects offered by the top five providers in 2017 alone!
19 March 2018
In the week of March 18-23 PSI welcomes 20 PhD students and postdocs taking part in
the HERCULES 2018 school on Neutron and Synchrotron Radiation. They will attend
lectures and perform two days of practical courses at several beam lines of the Swiss
27 February 2018
Classical theory predicts that supersaturated carbonate solutions consist mostly of ions and ion pairs, with a small number of larger clusters present in the solution. The population of the different sized clusters in a solution is solely defined by the cluster’s size dependent Free Energy. If clusters are large enough they serve as nucleation germs for a new solid phase. The nucleation occurs once the surface free energy barrier posed by the new solid-liquid interface is overcome by the free energy win from bulk phase growth. However, for calcium carbonate solutions, this classical view has been challenged by the emergence of non-classical theories. In a novel experiment, using synchroton X-ray absorption spectroscopy, the molecular structure around the solvated calcium ion in dilute supersaturated calcium carbonate solutions was probed in situ. The results obtained definitively show that supersaturated calcium carbonate solutions are dominated by ions and ion pairs. The presence of larger oligomers as predicted by non-classical theories was not detected. Moreover, predictions from independent theoretical calculations on the structure of supersaturated calcium carbonate solutions were in congruence with the experimental results. As a consequence, it is quite clear that the nucleation of calcium carbonate follows a classical pathway.
29 January 2018
Using a unique set of well-defined silica-supported Ni nanoclusters (1–7 nm) and advanced characterization methods it was proved how structure sensitivity influences the mechanism of catalytic CO2 reduction, the nature of which has been long debated.
7 December 2017
Media Releases Large Research Facilities SwissFEL
The years of careful planning and construction have paid off: At the newest large-scale research facility of the Paul Scherrer Institute PSI – the X-ray free-electron laser SwissFEL – the first experiment has been carried out successfully. With that, two goals have been achieved: First, a new scientific result is already expected. Second, the interaction of the many individual components of the highly complex facility is being optimised.
17 November 2017
Research Using Synchrotron Light Human Health
A spin-off from PSI has received this year's Swiss Technology Award: The young company GratXray is developing a new method for early diagnosis of breast cancer.
23 October 2017
The unexpected finding that in an ‘artificial spin ice’ magnetostatic energy can be transformed into directed rotation of magnetization provides fresh insights into such nano-patterned magnetic structures — and might enable novel applications in nanoscale devices.
17 October 2017
Fluid catalytic cracking catalysts, which are composite particles of hierarchical porosity, were examined using ptychographic X-ray tomography. These particles are essential to the conversion of crude oil into gasoline. Examination of catalysts at decreasing levels of catalytic conversion efficacy allowed the detection of possible deactivation causes.
17 October 2017
Current-induced spin-orbit torques hold a great potential for manipulation of magnetization at ultrafast timescales. Researchers at ETH Zürich have demonstrated, using time-resolved STXM imaging at the Swiss Light Source, the influence of spin-orbit torques on the switching behaviour of Pt/Co/AlOx
11 October 2017
Highly crystalline thin films of organic semiconductors offer great potential for high-performance, low-cost flexible electronics. Researchers at IMEC Belgium have developed a new double-step thin film fabrication process that offers higher performance devices. Soft X-ray spectro-microscopy at the Swiss Light Source was used to prove that the increased performance comes from larger areas of material sharing the same molecular orientation.
26 September 2017
Media Releases Energy and Environment Research Using Synchrotron Light Environment
PSI researchers have developed an experimental chamber in which they can recreate atmospheric processes and probe them with unprecedented precision, using X-ray light from the Swiss Light Source SLS. In the initial experiments, they have studied the production of bromine, which plays an essential role in the decomposition of ozone in the lower layers of the atmosphere. In the future, the new experiment chamber will also be available for use by researchers from other scientific fields.
1 September 2017
The SPS 2017 Prize in Condensed Matter Physics, sponsored by IBM, has been awarded to Dr. Nan Xu for his excellent work on topological quantum states. Dr. Nan Xu is a joint postdoc of Paul Scherrer Institute (PSI) and the École Polytechnique Fédérale de Lausanne (EPFL).
20 July 2017
Media Releases Materials Research Matter and Material Research Using Synchrotron Light
For the first time, scientists have made visible the directions of the magnetisation inside a 3D magnetic object. The smallest details in their visualisation were ten thousand times smaller than a millimetre. Among others, the magnetic structure contained one outstanding kind of pattern: magnetic singularities called Bloch points, which up to now were only known in theory.
17 July 2017
By combining a scalable cutting-edge synthesis method with time-resolved X-ray absorption spectroscopy measurements, it was possible to capture the dynamic local electronic and geometric structure during realistic operando conditions for highly active OER perovskite nanocatalysts.
13 July 2017
Lignin is a major constituent of plants, and may be used as a precursor for fuels and fine chemicals. Catalytic fast pyrolysis of lignin is one of the most promising approaches. By using vacuum ultraviolet synchrotron radiation and threshold photoelectron spectroscopy we could identify elusive intermediates, which are responsible for the formation of phenol and benzene and could thus tackle this reaction mechanism. Mechanistic understanding could enable targeted improvement of production methods in the future, beyond the currently used "cook-and-look" approach.
22 June 2017
A very thin layer on this beetle’s wings exhibits a complicated structure on the nanoscale that gives them a bright white color. X-ray nanotomography acquired at the Swiss Light Source provides a faithful image of this structure in three dimensions with which scientists can confirm its evolutionary optimization: just enough material for an efficient reflection of white light.
31 May 2017
Online combustion analysis relies heavily on spectral data to detect reactive intermediates isomer-selectively to establish e.g. kinetic flame models. Due to the difficulty to generate these species cleanly, spectral data are rather scarce. Here we report on the selective generation of three picolyl radical isomers (C5
*) by deamination of aminomethylpyridines. Picolyl radicals are relevant in biofuel combustion, and could now be characterized by threshold photoelectron spectroscopy using synchrotron radiation. Vibrationally resolved bands and distinct ionization energies allow for isomer-specific detection of these elusive species in complex environments and permit us to explore new avenues in soot- and NOx formation kinetics.
23 May 2017
Researchers from China and USA join forces with Swiss Light Source (SLS) macromolecular crystallography (MX) beamline scientists in a study, which aims at understanding an important step in the life cycle of the human betacoronavirus HKU1.
16 March 2017
Media Releases Materials Research Micro- and Nanotechnology Matter and Material Research Using Synchrotron Light
Researchers at the PSI have made detailed 3-D X-ray images of a commercially available computer chip. In their experiment, they examined a small piece that they had cut out of the chip beforehand. This sample remained undamaged throughout the measurement. It is a major challenge for manufacturers to determine if, in the end, the structure of their chips conforms to the specifications. Thus these results represent one important application of an X-ray tomography method that the PSI researchers have been developing for several years.
9 March 2017
A novel type of diffractive lenses based on interlaced structures enable x-ray imaging at resolutions below 10 nm. The fabrication method and the test results of these novel x-ray lenses have been published in the journal Scientific Reports
5 January 2017
Media Releases Energy and Environment Research Using Synchrotron Light Micro- and Nanotechnology
Eighty percent of all products of the chemical industry are manufactured with catalytic processes. Catalysis is also indispensable in energy conversion and treatment of exhaust gases. Industry is always testing new substances and arrangements that could lead to new and better catalytic processes. Researchers of the Paul Scherrer Institute PSI in Villigen and ETH Zurich have now developed a method for improving the precision of such experiments, which may speed up the search for optimal solutions.