Potential response of single successive constant-current-driven electrolytic hydrogen bubbles spatially separated from the electrode

The presence of bubbles in gas-evolving electrolytic processes can heavily alter the mass transport gaseous products and induce severe overpotential penalties at electrode through action bubble coverage (hyperpolarization) electrolyte constriction (Ohmic shielding). However, formation also alleviate by lowering concentration dissolved gas vicinity electrode. In this study, we investigate latter considering growth successive hydrogen driven a constant current alkaline-water electrolysis their impact on half-cell potential absence hyperpolarization. nucleate hydrophobic cavity surrounded ring microelectrode which remains free coverage. dynamics does not adhere to one particular scaling law time, but undergoes smooth transition from pressure-driven towards supply-limited growth. contributions different bubble-induced phenomena leading rich behaviour periodic fluctuations are identified throughout stages lifetime, influence size applied Ohmic components is quantified. We find that efficiency absorption, hence concentration-lowering effect, increases with increasing current. effect always eventually countered overcome shielding as outgrows eclipses beneath.