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

SENSORS AND ACTUATORS B-CHEMICAL

卷:296

Article

Filotas, Daniel^1,2  Maria Fernandez-Perez, Bibiana³  Nagy, Livia^1,2  Nagy, Geza^1,2  Souto, Ricardo M.^3,4 

[1] Univ Pecs, Fac Sci, Dept Gen & Phys Chem, Ifjusag Utja 6, H-7624 Pecs, Hungary

[2] Univ Pecs, Janos Szentagothai Res Ctr, Ifjusag U 20, H-7624 Pecs, Hungary

[3] Univ La Laguna, Dept Chem, POB 456, E-38200 Tenerife, Canary Islands, Spain

[4] Univ La Laguna, Inst Mat Sci & Nanotechnol, E-38200 Tenerife, Spain

关键词: SECM;    Ion selective microelectrode;    Galvanic corrosion;    pH distribution;    Mg dissolution;    Magnesium;   

DOI  :  10.1016/j.snb.2019.126625

来源: Elsevier

【 摘 要 】

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. In this way, the impact of the overestimated acidification accompanying metal dissolution using conventional tips was established from model experiments using non ion-sensitive open micropipettes and pH antimony microelectrodes. It is shown that the simultaneously acquired pH and pMg maps provide complementary information on the spontaneous and galvanic corrosion of AZ63 magnesium alloy.

【 授权许可】

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