Promotor: G. J. Kroes

Aiming to advance the development and deployment of a scalable, safe, and integrated hydrogen infrastructure to support the energy transition.

Heterogeneous catalysis is essential to many industrial applications. These catalysts are often comprised of supported nanoparticles, which contain various different surface sites.

This thesis investigates the interplay between high-redshift quasars and the intergalactic medium (IGM) during the Epoch of Reionization (EoR). It combines new observations, systematic measurements, and forward modeling to constrain the physical state of hydrogen in the early Universe.