Do magnetic moments in RuO2(110) and in 3d-transition metal perovskite oxides determine the high efficiency in oxygen catalysis?
Background: Electrolysis of water is a potential source for hydrogen production on a large scale. A measure of the inefficiency in electrolysis is the so called overpotential, the voltage needed to drive the process in excess of the voltage under thermodynamical equilibrium conditions. The contribution to the overpotential of the oxygen evolution dominates overwhelmingly. Magnetic oxygen is produced from nonmagnetic water, thus the role of surface magnetism could be highly relevant. Neither water nor hydrogen is magnetic, so oxygen can only be produced in an excited nonmagnetic state without violating conservation of angular momentum. For nonmagnetic anodes, the high overpotential can be associated with the notion that oxygen is produced initially in its nonmagnetic excited state and decays slowly to the ground state by higher order processes. A mechanism or a proper understanding for the high catalytic activity of e.g. RuO2 and oxide perovskites is still unknown, but recently de Groot et al. [J. Phys. Chem. C117, 6353 (2013)] proposed a very interesting idea: magnetic moments are at play.
Goal of the project: A detailed study to correlate the specific atomic sites and their magnetic identity with water dissociation on RuO2(110) and transition metal oxide surfaces with spin-polarized STM/STS and UPS (TU/e) will be combined with a more macroscopic performance study of the system with optical/transport measurements to determine the overpotential at the NWO institute DIFFER.
Setting: This research is set in a close collaboration between Dr. Kees Flipse of the M2N group at the TU/e and Dr. Anja Bieberle of the Dutch Institute for Fundamental Energy Research (DIFFER).
Requirements: The successful candidate will have:
- Bachelor and Master degrees in Physics with top grades. Candidates that are expected to obtain Master degree in Physics soon can also apply.
- A strong background in nano-physics and interest in physical chemistry. In particular, experience with scanning probe techniques and electrochemistry will be considered as an advantage.
- A strong motivation and independence to tackle and complete interdisciplinary research problems.
- The ambition to excel in research ranging.
- Excellent collaboration and communication skills.
For more information contact: Kees Flipse