Scientific Highlights

Neutron scattering experiments at three-axes spectrometers (TAS) investigate magnetic and lattice excitations by measuring intensity distributions to understand the origins of materials properties. The high demand and limited availability of beam time for TAS experiments however raise the natural question whether we can improve their efficiency and make better use of the experimenter’s time. 

The Smart Digital User (SDU) software for unattended data collection has been deployed at the macromolecular crystallography beamlines at the Swiss Light Source. 

Coacervation via liquid-liquid phase separation provides an excellent oppor- tunity to address the challenges of designing nanostructured biomaterials with multiple functionalities. Protein-polysaccharide coacervates, in particular, offer an appealing strategy to target biomaterial scaffolds, but these systems suffer from the low mechanical and chemical stabilities of protein-based condensates. Here we overcome these limitations by transforming native proteins into amyloid fibrils and demonstrate ...

Mobility of water, sodium and gas molecules within a smectite nanopore

Various gases are produced by metal corrosion and organic material degradation in deep gelological repository for nuclear waste. To ensure repository safety, it's important to demonstrate that gases can be dissipated by diffusion in host rocks and prevent pressure buildup in repository near field. Smectite mineral particles form a pore network that is usually saturated with water, making gas diffusion the primary transport mechanism. Molecular simulations have shown that the diffusion of gases through the pore network depends on various factors, including pore size and temperature. For instance, smaller pores and lower temperatures tend to reduce gas diffusion. Interestingly, hydrogen and helium have been found to diffuse faster than argon, carbon dioxide, and methane, possibly due to interactions with the clay surface and water molecules. Ultimately, the diffusion coefficients for different gases and pore sizes can be predicted using an empirical relationship, which is useful for macroscopic simulations of gas transport.

20 international students visited PSI as part of the renowned Hercules School to learn about our state-of-the-art techniques and methodologies at our large scale facilities.

The conversion efficiency for green hydrogen production in a polymer electrolyte water electrolyzer (PEWE) is strongly influenced by the ohmic cell resistance and therefore the thickness of the membrane. The use of thin membranes (~50 micron or below) is limited by gas crossover of H₂ and O₂, which can lead to the formation of an explosive gas mixture. The incorporation of a Pt recombination catalyst provides remedy and allows a more dynamic operating mode (cf. Highlight 03/2022). However, the presence of Pt nanoparticles leads to an increase in the rate of membrane degradation. Therefore, we have additionally doped the membrane with cerium-zirconium-oxide (CZO) nanoparticles, which act as radical scavenger. The rate of membrane degradation can thus be reduced.