Energy and Environment Research Division (ENE).
Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. Technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, environmental and social consequences, for both present and future energy supply systems.
Division Head: Prof. Dr. Thomas Justus Schmidt
Newly discovered rapid particle growth rates may be the answer to the mystery of aerosol formation in urban smog
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.
PSI researchers went to the Jungfraujoch research station and applied in situ measurement techniques in real clouds to investigate the ability of soot particles to form cloud droplets. This is a key process determining the atmospheric life-cycle of soot particles, which are primarily emitted by combustion engines and which have a warming effect on climate by absorbing solar radiation.
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.
Award conferred by SwissLung.org during the award ceremony in Berne, Switzerland
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.
Kinetics and Mechanism of Metal Nanoparticle Growth via Optical Extinction Spectroscopy and Computational Modeling: The Curious Case of Colloidal Gold
An overarching computational framework unifying several optical theories to describe the temporal volution of gold nanoparticles (GNPs) during a seeded growth process is presented. To achieve this, we sed the inexpensive and widely available optical extinction spectroscopy, to obtain quantitative kinetic data. In situ spectra collected over a wide set of experimental conditions were regressed using the hysical model, calculating light extinction by ensembles of GNPs during the growth process. This model rovides temporal information on the size, shape, and concentration of the particles, and any electromagnetic interactions between them. Consequently, we were able to describe the mechanism of GNP growth and divide the process into distinct genesis periods. We provide explanations for several longstanding mysteries, e.g., the phenomena responsible for the purple-greyish hue during the early stages of GNP growth, the complex interactions between nucleation, growth and aggregation events, and a clear distinction between agglomeration and electromagnetic interactions. The presented theoretical formalism has been developed in a generic fashion so that it can readily be adapted to other nanoparticulate formation scenarios such as the genesis of various metal nanoparticles.