In this section
@article{Li:2024:10.1016/j.corsci.2024.112524,
author = {Li, B and Harrison, NM and Horsfield, AP},
doi = {10.1016/j.corsci.2024.112524},
journal = {Corrosion Science},
title = {Uncovering the electrochemical stability and corrosion reaction pathway of Mg (0001) surface: insight from first-principles calculation},
url = {http://dx.doi.org/10.1016/j.corsci.2024.112524},
volume = {241},
year = {2024}
}
TY - JOUR
AB - An understanding of the anomalously enhanced hydrogen evolution reaction (HER) of magnesium (Mg) underanodic polarisation in aqueous corrosion is paramount for a predictive theory of its corrosion and metalelectrocatalysis. Previous theoretical and experimental studies have proposed that sub-surface hydride phasesplay a role in this behaviour but the underlying atomic mechanisms remain unclear. By constructing theoreticalsurface Pourbaix diagrams, based on density functional theory (DFT) calculations, we have identified theatomic structure of a sub-surface hydride phase on the Mg (0001) surface that remains electrochemicallystable under significant anodic overpotentials across a wide pH range. Specifically, this stability persists upto 0.38 VSHE under mildly alkaline conditions (e.g., pH = 8), thus providing thermodynamic support forthe proposed hydride-enhanced HER under anodic conditions. Reaction barrier analysis establishes that theproposed sub-surface hydride phase could promote anodic HER via a Heyrovsky pathway, based on hydrogenoutward diffusion, with an energy barrier of 1.54 eV as the rate-limiting step, showing an anodic characteristicand significantly favouring external anodic polarisation. Furthermore, we have established that the surfaceadsorption condition, contingent on both the pH and potential, significantly influences the mechanism andkinetics of the initial corrosion of Mg.
AU - Li,B
AU - Harrison,NM
AU - Horsfield,AP
DO - 10.1016/j.corsci.2024.112524
PY - 2024///
SN - 0010-938X
TI - Uncovering the electrochemical stability and corrosion reaction pathway of Mg (0001) surface: insight from first-principles calculation
T2 - Corrosion Science
UR - http://dx.doi.org/10.1016/j.corsci.2024.112524
VL - 241
ER -
