Scientific Highlights
Mechanism For All-Optical Magnetization Switching
X-rays reveal a non-collinear magnetic state as the base for all-optical magnetization switching.
New Nat. Rev. Phys. publication: A “gold standard” for computational materials science codes
A large consortium of scientists, coordinated by PSI researchers in the LMS laboratory, led the most comprehensive verification effort so far on computer codes for materials simulations, providing their colleagues with a reference dataset and a set of guidelines for assessing and improving existing and future codes.
A gold standard for computational materials science codes
The most comprehensive verification effort so far on computer codes for materials simulations.
Park Innovaare Cleanroom Name is: PICO
We are happy to announce that the new Cleanroom Name in the Park Innovaare will be PICO = Park Innovaare Cleanroom for Optics and innovation.
Next Step – we will work on a Logo (ideas welcome), together with PiA.
The winner of the naming contest: Helmut Schift
A more efficient degrader for proton therapy
At PSI’s Center for Proton Therapy (CPT), protons are used to treat cancerous tumours in a highly targeted way that spares healthy tissue as much as possible. This is the result of the characteristic way in which charged particles interact with matter, so that a beam of protons deposits most of its energy at a certain depth in a material depending on the energy and the composition of the material. The dedicated medical cyclotron COMET accelerates protons to an energy of 250 MeV, which then have to be "slowed down" so that the energy matches the depth of the tumour to be treated.
Cobalt-free layered perovskites RBaCuFeO5+d (R = 4f lanthanide) as electrocatalysts for the oxygen evolution reaction
Co oxides with perovskite-related structure are particularly promising, cost-effective OER catalysts. However, the increasing Co demand by the battery industry is pushing the search for Co-free alternatives. Here we investigate the potential of the Co-free layered perovskite family RBaCuFeO5+δ (R = 4f lanthanide), where we identify the critical structural and electronic variables leading to high OER catalytical performance. The employed methodology, based in the use of advanced neutron and X-ray synchrotron techniques combined with ab initio DFT calculations allowed to reveal LaBaCuFeO5+δ as new, promising Co-free electroctalyst. Moreover, we could show that this material can be industrially produced in nanocrystalline form. We believe that the reported results and methodology may contribute to the implementation of new technologies aimed to generate energy with lower carbon emissions, and can also inspire the scientific community in their search of other Co-free materials with good OER electrocatalytical properties.
Additive manufacturing of alloys with programmable microstructure and properties
Using laser powder bed fusion (LPBF) technology, we devise special processing strategies to ‘program’ the thermal stability of the as-printed alloy, such that it is possible to decide, a priori, how the material’s microstructure will evolve upon heat treatment
Understanding the (de-)lithiation mechanism of nano-sized LiMn2O4 allows achieving long-term cycling stability
We report an in-depth investigation of the local atomic geometry, electronic and crystallographic structure evolution of nano-sized LiMn2O4 using operando XAS and XRD to shed light on (de-)lithiation mechanism when cycled in wide voltage range of 2.0 to 4.3 V vs Li+/Li. Leveraging on these findings, a novel electrochemical cycling protocol, with periodic deep discharge, yields superior electrochemical performance cycled in the range of 3.3 to 4.3 V exhibiting an excellent structure cyclability and an unprecedented increase in the specific capacity upon long cycling.
TEY-STXM confirms homogeneous doping of nanoparticles for non-fullerene organic solar cells
One of the challenges in modern research on the fabrication of non-fullerene acceptor based organic solar cells is the availability of very efficient hole transport layers (HTLs). A new approach that avoids mutual solubility issues is to deposit the HTL from a suspension of doped organic nanoparticles. Surface-sensitive TEY-STXM measurements at the PolLux beamline characterised the homogeneity of the dopant in the nanoparticles and develop efficient nanoparticle HTL materials for organic solar cells.
Investigations of the irradiation hardening on a ferritic model alloy from spherical nano-indentations
The objective of this project was to determine the contribution from a variety of obstacles to moving dislocations to the nano-indentation stress necessary to initiate plastic flow. The obstacles are characterized by different length scales. Among these characteristic lengths, there are those associated with the material microstructure such as grain size, dislocations density, irradiation-induced defects, and those related to the size of the plastic zone beneath the indenter, or equivalently to the size of the indent. Thus, we can classify the size effects into two categories: structural size effect and indentation size effect (ISE). The underlying idea is to quantify and separate these two effects on the unirradiated material first to be able to properly isolate the contribution of the irradiation defect on the measured hardness from the tests on irradiated materials.