Congratulations to Syed Sahil Hossain for his successful PhD defense

On May 12, 2023 Syed Sahil Hossain successfully defended his dissertation entitled "Dynamics of single hydrogen bubbles produced by water electrolysis". His work was done at the department of Transport Processes at Interfaces in Helmholtz Zentrum Dresden Rossendorf headed by Prof. Dr. et Ing. habil Kerstin Eckert and supervised by Dr.-Ing. Gerd Mutschke.

Detailed understanding of bubbles growing on a solid surface is a fundamental requirement in many technological domains, with particular application to water electrolysis and its emerging significance for a clean energy transition. Evolution of bubbles at the electrode surface greatly determines the overall efficiency and throughput of an electrolysis cell. Bubbles residing on the electrode surface create electrical resistance and reduce the active electro-catalytic area. Therefore, fast removal of the bubbles is desirable for efficient operation. With this motivation, Syed Sahil Hossain’s dissertation aimed to build a deeper understanding of the bubble dynamics during the pre-detachment and detachment stages.

In his work, single hydrogen bubbles grown on microelectrodes are chosen as the object of study. Thermocapillary and electric forces acting on an electrolytic bubble are introduced, and a dynamical model of the bubble motion is developed. By means of mathematical and physical modeling of the forces, a working mechanism is provided for a novel mode of oscillatory bubble detachment. To summarize, this dissertation provides a systematic framework for characterizing forces acting on the bubble and investigating the dynamics of the bubble motion. Thereby, it adds to our current understanding of bubble evolution and takes one step towards predictive detachment models.