Oxygen bubble removal using electrode vibration for improved water oxidation performance

Porous transport electrode (PTE) is an innovative electrode category which presents a tortuous surface. That peculiar characteristic increases the availability of the electrode surface during the electrochemical hydrogen production process by electrolysis of water and favours the hydrogen bubble detachment from the surface. The presence of hydrogen bubbles reduces the electrolyser efficiency. Nowadays, on the market, there are many different types of PTE but there is a lack of analytical methods to distinguish their performances. To determine their performance differences, a system that involves the use of mechanical vibration directly applied to the PTE in a three-electrode setup is created. For the analysis three different electrode materials are selected: Ni-Veco, Ni-foam and Ni-felt. Analytical methods are developed and applied to identify the most active PTE, thus the PTE less affected by the presence of bubbles on its surface. Then, the system is applied to the electrochemical activation phase. The PTEs activated with the use of mechanical vibration have enhanced performances. The thesis was entirely carried out at Catalytic and Electrochemical Processes for Energy Applications (CEPEA) at the Dutch Institute For Fundamental Energy Research (DIFFER), The Netherlands, under the local supervision of Michail Tsampas and Sina Haghverdi Khamene.