Congratulations to Hannes Rox for his successful PhD defense

On December 15, 2025, Dipl.-Ing. Hannes Rox successfully defended his dissertation on the topic “Towards membraneless alkaline water electrolysis by improved bubble management.”

Alkaline water electrolysis remains the most mature technology for the large-scale production of high-purity green hydrogen. This is needed to replace fossil fuels with renewable energy sources in the transition to an emission-neutral industry. To reduce costs and improve efficiency, a promising approach is to minimize bubble-induced losses. By combining optimization of the electrode surfaces and the cell geometry of membraneless electrolyzers, the bubbles could be removed from the cell much more effectively. This led to a significant improvement in cell voltage. At the same time, the blocking of catalytically active centers by adhering bubbles was reduced by spatially decoupling the catalytically active centers from the active bubble nucleation centers. The results of this work are therefore an important contribution to the energy transition.