In water electrolysis, hydrogen and oxygen bubbles may form and grow at the electrode surfaces. The adhesion of these bubbles at the electrodes reduces the reaction area and impedes mass transfer, causing additional energy losses of up to 25%. We perform direct numerical simulations to investigate the behaviour of surface bubbles in electrochemical environments by using a volume-of-fluid (VOF) method implemented in Basilisk [1]. The numerical model considers multi-physical phenomena including mass transfer, electrode reaction, and interface dynamics. We simulate bubbles growing on nano-/micrometre-sized electrodes resembling catalytic islands to investigate bubble phenomena at different length scales, including nucleation, growth, directional motion along the electrode [2,3], and discuss how to effectively regulate the bubble behaviour and to accelerate their detachment from the electrode surface. Different influencing factors are considered, such as wettability, electrode geometry, electrolyte composition, and the applied electric field. Our results show that micro-/nano-structuring of electrodes, hydrophicility of the electrode surfaces, and a moderate electric field are beneficial for reducing the bubble adhesion. Our findings provide insights into reducing the bubble-related energy losses and enhancing the efficiency of the electrolysis [4]. REFERENCES [1] S. Popinet. The basilisk code. Available at http://basilisk.fr/, 2003. [2] Y. Ma, M. Huang, G. Mutschke, X. Zhang. Nucleation of surface nanobubbles in electrochemistry: Analysis with nucleation theorem. J. Colloid. Int. Sci., Vol. 654, pp. 859-867, 2024. S. Popinet. The basilisk code. Available at http://basilisk.fr/, 2003. [3] M. Huang, M. Xu, Y. Han, X. Zhang, M. Rudolph, K. Eckert and G. Mutschke. Numerical simulation of surface bubble growth at micro-cavities. Chem. Eng. Sci., Vol. 321, p. 122856, 2026. [4] M. Huang, C. Sun, K. Eckert, X. Zhang and G. Mutschke. Dynamic equilibrium of electrochemical bubbles growing on micro-electrodes. J. Fluid Mech., Vol. 1011, p. A23, 2025.