Lab News & Scientific Highlights

Whitlockite in mammary microcalcifications

Whitlockite in mammary microcalcifications is not associated with breast cancer

Microcalcifications, small deposits of calcium-containing minerals that form in breast tissue, are often, but not always, a warning sign of breast cancer. The relationship between microcalcifications and cancer has not been fully understood thus far. Researchers discovered now that the relationship between microcalcifications and tumors seems to be linked to the presence of a particular mineral called whitlockite, which is rich in magnesium and is found in microcalcifications only in the absence of tumors.

Figure 1: Branching during the reaction mechanisms of the catalytic pyrolysis of guaiacol. The Bronsted acid site density is responsible, which reaction route is taken.

Unveiling the reaction mechanism shines light on the selectivity increase in catalytic processes

Increasing the selectivity of a chemical process through rational catalyst design is the Holy Grail of heterogeneous catalysis. Researchers at PSI and ETH Zürich showcase how revealing hidden steps in reaction pathways can steer processes towards preferred products, as demonstrated in a study focused on biomass valorization.

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Tracking chemical bond changes with element selectivity and in real time

X-ray photoelectron spectroscopy probes the chemical environment in a molecule at a specific atomic site. Now the concept is extended with a site selective trigger to follow chemical bond changes as they occur on the femtosecond time scale.

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PSI researcher Patrick Hemberger honored in the Rising Stars special issue in Energy & Fuels

To celebrate contributions of highly influential early and mid-career researchers in energy research, the journal Energy & Fuels established an annual recognition of Energy and Fuels Rising Stars.

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Finding Ketenes in the Methanol to Olefins Process

How are the first olefins formed in the early stages of the methanol-to-olefins process? Detection of two reactive ketene species solves this long-standing puzzle.

Hercules School 2022 group photo

Hercules School 2022

PSI hosted again the Hercules School in March 2022. We had the pleasure to welcome 20 international PhD students, PostDocs and scientists to demonstrate our state-of-the-art techniques and methodologies at our large scale facilities, the Swiss Light Source (SLS), the Swiss Spallation Neutron Source (SINQ) and our free electron laser SwissFEL.

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Watch them growing: New mechanistic insights into catalytic methane coupling

Methane valorization is a promising technology to utilize this platform compound to produce aromatics and hydrocarbons. Researchers from PSI and ETH Zürich unveiled this reaction mechanism and observed the molecular growth from the ground up. Besides stepwise CH3 addition,  novel routes involving the dimerization of resonantly stabilized propargyl (C3H3) radicals to benzene (C6H6) were identified. These mechanistic insights will aid the development of valorisation strategies.

A Three Dimensional View of Chemical Heterogeneities in Defect-Engineered HKUST-1 Crystals

Full-field X-ray absorption tomography reveals the chemical structure of defects in metal-organic frameworks

Cryo-full-field XANES computed tomography was used to visualize the presence and distribution of a second coordination polymer of reduced copper coordination within defect-engineered HKUST-1 MOF crystals. Observations encourage a revisitation of the structure-property relationships of defect-engineered MOFs.

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Important elementary reactions of lignin catalytic pyrolysis revealed

To develop sustainable lignin valorization strategies, a solid understanding of the underlying reaction mechanism is critical. By detection of highly reactive and elusive intermediates, new light could be shed on one of the most basic elementary reactions in lignin catalytic fast pyrolysis.

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HERCULES SCHOOL 2021 AT PSI

During the week of March 15 – 19, we had the pleasure to welcome 20 international PhD students, PostDocs and assistant professors at PSI, taking part in the first virtual HERCULES SCHOOL on Neutrons & Synchrotron Radiation.

Pazyryk carpet fibre

Insights into the world’s oldest pile carpet

High-resolution XRF imaging of the specific metal distribution within wool fibers at the PHOENIX beamline gives insights into traditional oriental dyeing procedures.

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Clocking the movement of electrons inside an atom

Scientists pioneer an approach called self-referenced streaking, clocking Auger electrons with sub-femtosecond resolution. The breakthrough will unlock the broader potential for attosecond time resolution at X-ray free-electron lasers.

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Key activity descriptors of nickel-iron oxygen evolution electrocatalysts in the presence of alkali metal cations

Ni-Fe oxyhydroxide is among the most active oxygen evolution electrocatalysts. Electrolyte alkali metal cations modify the activity and reaction intermediates, however, the exact mechanism is at question due to unexplained deviations from the cation size trend. Our X-ray absorption spectroelectrochemical results show that the OER activity follows the variations in .electrolyte pH rather than a specific cation. Our DFT-based reactivity descriptors confirm the conclusions of an indirect pH effect.

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Ruzicka Prize

The Ružička ​Prize 2020 goes to Dr. Patrick Hemberger (PSI) for his research on understanding the mechanisms of catalytic fast pyrolysis by unveiling reactive intermediates in heterogeneous catalysts.

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Spin cascade and doming in ferric hemes

In biology, structure and function are closely interwoven. A case in point is oxygen transport in the lungs, which relies on ferrous heme proteins adopting dome-like shapes.

First light at Maloja endstation

First light in the SwissFEL Maloja endstation

The first endstation at the SwissFEL Athos soft X-ray branch is rapidly developing and on track for first experiments in 2021.