Multi-barrel electrodes containing an internal micro-reference for the improved visualization of galvanic corrosion processes in magnesium-based materials using potentiometric scanning electrochemical microscopy

Simultaneous monitoring of pH and Mg2+ distributions above AZ63 magnesium alloy, either spontaneously corroding or galvanically coupled with iron, was achieved using SECM in the potentiometric operation. By introducing an internal micro-reference electrode in a multi-barrel arrangement of the ion-selective microelectrode used as scanning probe, superior performance was achieved compared to conventional single-barrel and double-barrel assemblies....