Local enhancement of hydrogen production by the hydrolysis of Mg17Al12 with Mg “model” material

Serge Al Bacha (1, 2, 3, 4) , Eliana Desireé Farias (5) , Philippe Garrigue (5) , Mirvat Zakhour (4) , Michel Nakhl (4) , Jean-Louis Bobet (1) , Dodzi Zigah (6, 5)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
3 ILV - Institut Lavoisier de Versailles
4 LU / ULB - الجامعة اللبنانية [بيروت] = Lebanese University [Beirut] = Université libanaise [Beyrouth]
5 ISM - Institut des Sciences Moléculaires
6 IC2MP [Poitiers] - Institut de chimie des milieux et matériaux de Poitiers [UMR 7285]

The effect of galvanic coupling on the corrosion behavior of Mg and Mg17Al12 in Mg-Al alloys was studied by Scanning ElectroChemical Microscopy (SECM). The effect of galvanic coupling between Mg and Mg17Al12 was investigated using a “model” Mg+Mg17Al12 material with a controlled microstructure to evaluate the hydrogen evolution at a micrometric scale. SECM maps revealed that galvanic coupling between Mg and Mg17Al12 accelerates the corrosion rate (formation of a thicker passive layer) of both components. Mg17Al12 acts controversially to a conventional cathode in galvanic system since hydrogen production by its hydrolysis reaction was found to increase due to the electron transfer with the anode (Mg).

Mots clés: SECM; Galvanic coupling; Corrosion; Mg; Mg17Al12; Hydrogen production

Domaines: Matériaux

Serge Al Bacha, Eliana Desireé Farias, Philippe Garrigue, Mirvat Zakhour, Michel Nakhl, et al.. Local enhancement of hydrogen production by the hydrolysis of Mg17Al12 with Mg “model” material. Journal of Alloys and Compounds, 2022, 895, pp.162560. ⟨10.1016/j.jallcom.2021.162560⟩. ⟨hal-03431198⟩