Lecture

Van Marum Colloquium: Experimental modelling of (photo-)catalysts for challenges in the energy transition: The surface science of Ti and Mo-based sulfide and oxide (nano)catalysts

Dr. Lars Mohrhusen (Carl von Ossietzky Universität Oldenburg)

Date: Monday 24 February 2025
Time: 14:00 - 15:00
Location: Gorlaeus Building
Einsteinweg 55
2333 CC Leiden
Room: CM.3.23

Abstract

To overcome some of the current challenges especially in the energy transition, heterogeneous (photo)catalysis is a key technology. However, for many relevant processes, we are still lacking the optimal catalyst materials, that are cheap and available, long-term, stable and nontoxic, but very reactive and ideally selective.

In my research, one target is to develop such materials based on rational material design, also called the surface-science approach: To overcome experimental limitations under technical conditions (such as high pressures and temperatures, complex and heterogeneous materials with a multidimensional structure, dynamic changes, …), we investigate model systems by using well-defined (single crystal) samples under ultra-high vacuum (< 10-9 mbar) or so-called operando conditions (usually few mbars). Combining insights from spectroscopy, microscopy and reactivity studies can then gain a comprehensive picture down to the atomic level. ^{1,2, 3}

In this lecture, I will briefly introduce this research concept and present examples based on materials relevant in view of the current energy challenges. First, atomic level studies on the deactivation of MoS₂-based nanoparticles under oxyreductive hydrotreatment conditions will be summarized, being one of the current limitations for the industrial application of hydrotreatments of oxygen- and nitrogen-rich biooils³ necessary to convert biomass to sustainable fuels for heavy transportation. Second, recent results on Ti-based hybrid systems for photocatalytic reactions will be presented. Therein, the role of point defects such as Ti3+ for the adsorption of small molecules and subsequent bond activation will be illuminated.⁴ In addition to oxides, nanostructured two-dimensional TiS₂ will be introduced as a potential candidate for future photocatalytic applications.⁵

References

L. Mohrhusen, T. Egle, J.D. Lee, C. M. Friend, R. J. Madix, J. Phys. Chem. C 2022, 126, 48, 20332– 20342.
L. Mohrhusen, S. Zhang, M. M. Montemore, R. J. Madix, Small 2024, 2405715.
M. Hedevang, L. Mohrhusen, F. Hallböök, D, Gajdek, L. Merte, S. Blomberg, J.V. Lauritsen, to be submitted.
L. Mohrhusen, K. Al-Shamery, Catal. Lett. 2023, 153, 2, 321-337.
N. Kruse, K. Hazeldine, D. Le, M. Hedevang, T. Rahman, J. V. Lauritsen, L. Mohrhusen, to be submitted.