Combining magnetic and superconducting functionalities enables lower energy spin transfer and magnetic switching in quantum computing and information storage, owing to the dissipationless nature of quasi-particle mediated supercurrents. Here, we put forward a system where emergent spin-ordering and diffusion of Cooper pairs are achieved at a non-intrinsically magnetic nor superconducting metallo-molecular interface.
Correlation between Oxygen Vacancies and Oxygen Evolution Reaction Activity for a Model Electrode: PrBaCo2O5+δ
The role of the perovskite lattice oxygen in the oxygen evolution reaction (OER) is systematically studied in the PrBaCo2O5+δ family. The reduced number of physical/chemical variables combined with in-depth characterizations such as neutron dif-fraction, O K-edge X-ray absorption spectroscopy (XAS), electron energy loss spectroscopy (EELS), magnetization and scanning transmission electron microscopy (STEM) studies, helps investigating the complex correlation between OER activity and a single perovskite property, such as the oxygen content. Larger amount of oxygen vacancies appears to facilitate the OER, possibly contributing to the mechanism involving the oxidation of lattice oxygen, i.e., the lattice oxygen evolution reaction (LOER). Furthermore, not only the number of vacancies but also their local arrangement in the perovskite lattice influences the OER activity, with a clear drop for the more stable, ordered stoichiometry.
Every year, during the winter months, PhD students of the Swiss Nanoscience Institute take part in the SNI: Nano in the snow PhD school. Currently, as COVID-19 is still omnipresent in our everyday it happened virtually this year and Thomas Mortelmans took part. He said: “It was an exciting day filled with excellent scientific content from a variety of research fields; ranging from quantum physics, to protein engineering and drug delivery. During these events, the interdisciplinary of SNI is nicely highlighted and the benefit of joined research projects across scientific disciplines can be seen.”
Thomas gave an interdisciplinary introduction to the field of microfluidics and was awarded with the prize of best talk.
The compounds known as ‘pyrazinacenes’ are simple, stable compounds that consist of a series of connected nitrogen-containing carbon rings. They are suitable for applications in electrochemistry or synthesis, as the researchers describe in the science journal Communications Chemistry. They were first designed, synthesized and chemically characterized in solution by the Hill team and carefully investigated by Scanning Tunneling Microscopy and Surface Chemical Analysis. The compounds have been shown to reversibly release and accept electrons and arrange themselves differently depending on the oxidation state. Interestingly, the oxidation and reduction reactions of the pyrazinacenes are not only affected by a chemical impulse, but can also be stimulated by light so they can be considered photo-redox active.
Single atom catalysts hold great promise as O2- or CO2-reduction electrocatalysts, but a deeper understanding of their active sites’ structure and electronic properties is needed in order to render them sufficiently active and stable. To this end, we have used X-ray emission spectroscopy to determine these catalysts’ electronic configuration, and performed in situ measurements that unveil the effect of potential on this key feature.
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.
PbMO3 (M = 3d transition metals) family shows systematic variations in charge distribution and intriguing physical properties due to its delicate energy balance between Pb 6s and transition metal 3d orbitals. However, the detailed structure and physical properties of PbFeO3 remain unclear. Herein, we reveal that PbFeO3 crystallizes into an unusual 2ap × 6ap × 2ap orthorhombic perovskite super unit cell with space group Cmcm.
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.
The unconventional normal-state properties of the cuprates are often discussed in terms of emergent electronic order that onsets below a putative critical doping of xc≈0.19. Charge density wave (CDW) correlations represent one such order; however, experimental evidence for such order generally spans a limited range of doping that falls short of the critical value xc, leading to questions regarding its essential relevance. Here, we use X-ray diffraction to demonstrate that CDW correlations in La2−xSrxCuO4 persist up to a doping of at least x=0.21.