Gas bubbles are typically treated as insulating elements in electrochemical systems, yet their behaviour under confinement remains largely unresolved. In this work, we use electrochemical impedance spectroscopy to investigate charge transport at the interface formed between a nitrogen bubble and a platinum ultramicroelectrode. Our measurements reveal that electrical conduction is maintained across the bubble–electrode contact through a thin aqueous layer, whose resistance decreases markedly as the bubble is mechanically compressed. The reduction in junction resistance upon compression indicates that ionic transport within the confined liquid region is strongly influenced by bubble deformation. These observations suggest that mechanical changes in the bubble alter interfacial ion organisation and the effective thickness of the conducting layer. Importantly, the evolution of the impedance response with deformation shows a systematic dependence consistent with changes in the interfacial mechanical properties of the bubble.
These observations indicate a coupling between bubble mechanics, interfacial ion organisation, and electrical transport at gas–liquid–solid contacts. This correlation points to the possibility of exploiting impedance-based measurements at deformable bubble contacts as a new, local method for probing surface tension in gas–liquid systems. This study highlights gas bubbles as electrochemically active interfaces and introduces an electrochemical framework for accessing interfacial mechanical properties.