RT info:eu-repo/semantics/article T1 Potentiometric scanning electrochemical microscopy for the local characterization of the electrochemical behaviour of magnesium-based materials A1 Souto, Ricardo Manuel A1 Izquierdo Pérez, Javier A1 Nagy, Lívia A1 Bitter, István A1 Nagy, Géza K1 potentiometric SECM K1 magnesium K1 pH K1 ion selective micropipettes K1 antimony electrode AB The applicability of scanning electrochemical microscopy for the local detection and quantification of relevant species participating in the corrosion of magnesium-based materials is presented. The iron-magnesium galvanic pair exposed to aqueous NaCl solution was adopted as model system for this purpose. Mg2+ ion concentration and pH profiles were investigated using ion selective electrodes, containing a liquid membrane and Sb/Sb2O3 as sensor elements, respectively. Oxygen consumption at the substrate related to the cathodic reaction was also monitored with the antimony-based electrode though operated amperometrically. Data show a major production of hydroxyl anions at the cathodic sites as result of the oxygen reduction half-reaction, whereas in the vicinity of the magnesium surface pH is greatly affected by the anodic dissolution process instead. The later produces the release of metal cations accompanied by hydrogen evolution. YR 2013 FD 2013 LK http://riull.ull.es/xmlui/handle/915/19170 UL http://riull.ull.es/xmlui/handle/915/19170 LA en DS Repositorio institucional de la Universidad de La Laguna RD 17-nov-2024