Details of a crucial reaction: Physicists uncover oxidation process of carbon monoxide on a ruthenium surface
This illustrates a moment captured for the first time in experiments at SLAC National Accelerator Laboratory. The CO-molecule and oxygen-atoms are attached to the surface of a ruthenium catalyst. When hit with an optical laser pulse, the reactants vibrate and bump into each other and the carbon atom forms a transitional bond with the lone oxygen center. The resulting CO2 detaches and floats away. © SLAC National Accelerator Laboratory
An international team has observed the elusive intermediates that form when carbon monoxide is oxidized on a hot ruthenium metal surface. They used ultrafast X-ray and optical laser pulses at the SLAC National Accelerator Laboratory, Menlo Park, California. The reaction between carbon monoxide and adsorbed oxygen atoms was initiated by heating the ruthenium surface with optical laser pulses. Directly afterwards, changes in the electronic structure of oxygen atoms were probed via X-ray absorption spectroscopy as they formed bonds with the carbon atoms.The observed transition states are consistent with density functional theory and quantum oscillator models.
The researchers were surprised to see so many of the reactants enter the transition state - and equally surprised to discover that only a small fraction of them go on to form stable carbon dioxide. The rest break apart again. "It's as if you are rolling marbles up a hill, and most of the marbles that make it to the top roll back down again," says Anders Nilsson, professor at the SLAC/Stanford SUNCAT Center for Interface Science and Catalysis and at Stockholm University, who led the research.
A team from the Institute of Methods and Instrumentation in Synchrotron Radiation Research from HZB has contributed in this research activities at SLAC sponsored by the Volkswagen-Foundation and the Helmholtz Virtual Institute “Dynamic Pathways in Multidimensional Landscapes” in which HZB and SLAC collaborate.
“These results help us to understand a really crucial reaction with high relevance for instance for environmental issues and to see which role catalysts may play”, Martin Beye of the HZB Team explains.
See full press release at SLAC-Website
Citation: H. Öström et al., Science, 12 February 2015 (10.1126/science.1261747)
- The twisted nanotubes that tell a storyIn collaboration with scientists in Germany, EPFL researchers have demonstrated that the spiral geometry of tiny, twisted magnetic tubes can be leveraged to transmit data based on quasiparticles called magnons, rather than electrons.
- Ernst Eckhard Koch Prize and Innovation Award on Synchrotron Radiation 2025At the 27th BESSY@HZB User Meeting, the Friends of HZB honoured the dissertation of Dr Enggar Pramanto Wibowo (Friedrich-Alexander University Erlangen-Nuremberg). The Innovation Award on Synchrotron Radiation 2025 went to Prof. Tim Salditt (Georg-August-University Göttingen) and Professors Danny D. Jonigk and Maximilian Ackermann (both, University Hospital of RWTH Aachen University).
- Bright prospects for tin perovskite solar cellsPerovskite solar cells are widely regarded as the next generation photovoltaic technology. However, they are not yet stable enough in the long term for widespread commercial use. One reason for this is migrating ions, which cause degradation of the semiconducting material over time. A team from HZB and the University of Potsdam has now investigated the ion density in four different, widely used perovskite compounds and discovered significant differences. Tin perovskite semiconductors produced with an alternative solvent had a particular low ion density — only one tenth that of lead perovskite semiconductors. This suggests that tin-based perovskites could be used to make solar cells that are not only really environmentally friendly but also very stable.