Congratulations to Dr. Ellen Sterk for an Excellent PhD Defense. Rafael has successfully defended his PhD thesis, supervised by Prof. Bert Weckhuysen, prof. dr. E. Vogt, dr. I. Filot and dr. J. Louwen.

In her thesis, Ellen advanced the fundamental understanding of the structure-sensitive reaction mechanism of the Sabatier reaction (CO2 methanation). She studied four nickel surface facets—Ni(111), Ni(100), Ni(110), and Ni(211)—exploring both terrace and stepped surfaces of nickel metal nanoparticles. Through Density Functional Theory and Micro-Kinetics Modeling, she identified Ni(110) as the most active surface, capable of supporting multiple reaction pathways for CO* activation. Her research demonstrated that terrace facets showed minimal activity, with Ni(100) suffering from carbon poisoning, while Ni(211) showed moderate activity. She determined an ideal nanoparticle size of ~1.7 nm for CO2 methanation through Wulff-constructed nanoparticle analysis. Ellen refined micro-kinetic models by incorporating enthalpic corrections and lateral interaction penalties, aligning them with experimental data. She also investigated the vibrational behavior of reaction intermediates, providing a comprehensive frequency dataset for intermediates on nickel facets, valuable for understanding Ni-based catalysis in catalytic C1-reactions.

Ellen’s PhD thesis is available to read here.