News & Highlights

Kaspar Dällenbach, Scientist at the Laboratory of Atmospheric Chemistry (LAC) at the Paul Scherrer Institute (PSI) was granted the Ambizione Grant 2020 with his project “Particulate air pollution sources in low-income megacities (PRESSING)”.

Climate change is one of the biggest challenges humanity is facing. It requires an approach, in which competences and capacities in research are combined across Switzerland to develop solutions for a transformation of our society towards net zero CO₂ emissions.

Alexander Muroyama, Postdoctoral Researcher at the Electrochemistry Laboratory (LEC) at the Paul Scherrer Institute has successfully applied for the Ambizione Grant 2020 with his project “A novel process for electrochemical direct-air capture of CO₂”.

Patrik Winiger, Research Grant Advisor and Project Manager at ETH Zurich, successfully applied for the Ambizione Grant 2020 with the project “Macromolecular Aerosols in the Cryosphere from the Arctic to the Alps – MACrAA”. The idea was developed together with the Laboratory for Atmospheric Chemistry (LAC) at PSI. The LAC is a global leader in aerosol analytics and source identification. They own and operate a unique laboratory infrastructure with various instruments and multiple aerosol simulation chambers available for researchers.

With its Energy Strategy 2050 Switzerland aims – beside other goals – to promote the use of domestic renewable energy and to develop the electricity power grid, which plays a decisive role in the upgrading of the system of electricity power supply. A lot of research needs to be done to achieve these ambitious goals. An important research project in this area is ReMaP and its status quo was presented at the Paul Scherrer Institute PSI on 28 September.

Chemical changes inside of breathable airborne particles can cause reactive oxygen species (ROS) and carbon centered radicals (CCRs) to form, which are harmful to our bodies and induce oxidative stress in lungs. Using X-ray spectromicroscopy at the PolLux beamline and mimicking the environmental and sunlit conditions aerosol particles experience in the atmosphere near the Earth Surface, it was recently found that highly viscous organic particles with low water content can attain high concentrations of ROS and CCRs that persist over long times. Natural particles like these will occur in ambient humidity below 60% and effectively trap ROS and CCRs inside that react when exposed to light.

Platinum isolated atoms and clusters supported on molybdenum carbide have been characterized in situ by means of photoelectron spectroscopy. The presence of both species is essential to favor the stability, so that the catalysts displays high metal-normalized turnover number of 4,300,000 moles of hydrogen per mole of platinum during the water gas shift reaction.

Urs Baltensperger explains the background why it is absolutely necessary to wear masks in order to reduce the risk of beeing infected with Covid-19.

In the following you find the presentation and  summary

Spätestens seit Corona ist der Maskengebrauch auch in der Schweiz im Alltag präsent. Doch wie gut können wir uns und andere mit verschieden Materialien vor kleineren und grösseren Partikeln schützen? Das alljährlich durchgeführte PSI Feriencamp bietet Kindern einen spannenden Einblick in die faszinierende Welt der Forschung. In diesem Jahr gingen Kinder an einer Projektstation genau dieser Frage nach. Dabei untersuchten sie, wie gut verschiedene Materialien die im Labor generierten Partikel zurückhalten. Es wurden Textilmasken (im Handel erhältlich, wiederverwendbar, nicht FFP2-zertifiziert), Chirurgenmasken (Einwegmasken, FFP2-zertifiziert), Teefilter, Kaffeefilter, Papiertaschentuch und WC-Papier getestet, und es wurde klar, Maske ist nicht gleich Maske.

Atmospheric aerosols are considered the single largest uncertainty in assessing the human contribution to global warming and amongst the top five health risks worldwide. Our ability to investigate aerosol sources, their formation processes in the gas-phase, and their societal impacts is largely governed by our capability to measure their molecular constituents in real-time. Researchers at PSI have combined for the first time ultrahigh resolution mass spectrometry with high time resolution and sensitivity for the molecular analysis of aerosols.

Aerosols, suspended particles or droplets, play a key role in Earth’s atmosphere’s energy balance. They can also result in smog formation in cities, which leads to low visibility and serious health risks for the population. A recent study published in Nature outlines a newly discovered mechanism that may play a key role in the continued survival of particles in wintertime smog.

PSI researchers have designed and equipped a laboratory container for operation on research ships to undertake comprehensive studies of the chemistry and microphysics of the atmosphere. The floating laboratory was first deployed during the Antarctic Circumnavigation Expedition (ACE) with the aim of characterizing aerosol processes that are relevant for climate change in an atmosphere, which is hardly influenced by human emissions of air pollutants other than greenhouse gases.

Polymer electrolyte fuel cells (PEFC) are a key technology for the decarbonization of automotive mobility. In collaboration with Toyota, it is shown by dynamic, operando X-ray tomographic microscopy, how the liquid water saturation in modified gas diffusion layer materials is reduced.

The imaging data supports the understanding of the underlying mechanisms and explains improved cell performance. Novel instrumentation at the TOMCAT beamline  further improves imaging time resolution and allows for scan times as short as 0.1 s.

Researchers of the Laboratory for Catalysis and Sustainable Chemistry (LSK) from PSI have designed uneven probe supports, which reveal the hidden site of nanocrystals.

Their simple approach allows transmission electron microscopes (TEMs) complete access to the atomic structure of nanomaterials without the need for cumbersome experimental effort.

Investigation on early stage of solid formation from solution, before nucleation, have been carried out at PSI by small angle scattering technique using X-ray light from the Swiss Light Source SLS. The system under analysis was calcium carbonate, a model system archetype of several sparsely soluble inorganic materials and relevant in many field such as CO₂ capturing and biomineralization. The experimental setup, the method, and developed theoretical framework can be applied to many other systems and made available for the entire scientific community.

Scientists have just nucleated ice in an X-ray microscope for the first time and they created chemical maps of those responsible.

Wasserstoff gilt als vielversprechende Alternative für eine Zukunft ohne fossile Energieträger. Um Brennstoffzellen weiterzuentwickeln und für einen Markteintritt vorzubereiten, verstärkt die Empa die Zusammenarbeit mit der H2 Energy Holding AG und dem Paul Scherrer Institut (PSI).

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.

The interfacial ionization of strong acids is an essential factor of multiphase and heterogeneous chemistry in environmental science, cryospheric science, catalysis research and material science. Using Near Ambient Pressure X-ray Photoelectron (NAPP) spectroscopy, we directly detected a low surface coverage of adsorbed HCl at 253 K in both molecular and dissociated states and interpret the results as physisorbed molecular HCl at the outermost ice surface and dissociation occurring upon solvation deeper in the interfacial region. This study gives clear evidence for nonuniformity across the air−ice interface and questions the use of acid−base concepts in interfacial processes.

In contrast to nitrogen oxides, modern gasoline cars emit much more cancerogenic primary soot (black carbon + primary organic aerosol) and lead to more toxic secondary organic aerosol than modern diesel vehicles.

Although copper (Cu) was essential for the wealth of pre- and post-colonial societies in the Andes, the onset of extensive Cu metallurgy in South America is still debated. Based on a 6500 year ice-core Cu record from Illimani glacier in Bolivia we provide the first complete history of large-scale Cu smelting activities in South America. Earliest anthropogenic Cu pollution was found during the Early Horizon period ~700-50 BC. We attribute the onset of intensified Cu smelting in South America to the activities of the central Andean Chiripa and Chavin cultures ~2700 years ago. This study provides for the first time substantial evidence for extensive Cu metallurgy already during these early cultures.