Dr. Frederik Schiller, Centro de Física de Materiales (CSIC), San Sebastián, Spain, will give a talk on surface science and catalysis. The talk follows up the lecture given by Dr. Mohammed Al Sheikh Hamad, Yanbu University, Kingdom of Saudi Arabia (KSA):  Experimental Techniques in Physics on June 9th at 11:00 AM.

Abstract of Dr. Schiller's talk:

Ambient and Near-ambient pressure X-ray photoemission for advanced catalysts

One of the most pressing global challenges today is ensuring access to essential resources such
as food, water, infrastructure, and energy. Physics, chemistry, and materials science play a
crucial role in addressing these needs—particularly in the energy sector. Rising energy
demand, the depletion of fossil fuel reserves, and the environmental damage caused by
conventional energy sources (such as fossil fuels and nuclear power) are driving a sustained
push toward renewable energy. While technologies like solar and wind power are well
developed, their intermittent availability poses a major challenge. Effective energy storage
solutions are essential to ensure a stable and reliable energy supply. Hydrogen is often
proposed as a key solution to this storage problem. However, its highly explosive nature
presents safety concerns. One promising approach to overcome these drawbacks involves the
synthesis of artificial fuels using hydrogen combined with carbon (from CO₂) or nitrogen.
Although these transformation processes are known, their efficiency remains low. Catalysts—
materials that accelerate chemical reactions—have the potential to dramatically improve the
efficiency of these processes. In fact, catalysts are vital to the chemical industry as a whole,
enabling the production of numerous essential materials. While some catalysts have been
used for centuries, their mechanisms are still not fully understood. Gaining deeper insight into
how they work could lead to significant advancements in catalyst design, including improved
efficiency, reduced production costs, and greater availability.
In this talk, I will present our approach to studying catalysts for several fundamental but crucial
chemical reactions: CO oxidation, alkanol epoxidation, and ammonia conversion. To
investigate these processes, we utilize advanced photoemission techniques—primarily X-ray
photoemission spectroscopy (XPS) under ambient and near-ambient pressure conditions.
A distinctive aspect of our research is the use of curved single crystals. These are cylindrical
sectors of single crystals that contain both atomically flat regions and stepped areas with
systematically increasing step densities. This unique design allows us to explore how surface
structure influences catalytic activity. Our findings on such unusual substrates show that
surface steps can have varying effects depending on the reaction and the type of step. In some
cases, steps significantly enhance reaction rates, while in others, they inhibit reactivity.
Moreover, different types of steps can lead to distinct reaction kinetics.