Abstract
This study clarifies that the inner and outer layers of the anodic film consist of a nano/micro-porous MgO+Mg(OH)2 mixture. The film becomes thicker and more porous with increasing potential. It can rupture when potential is too positive in a non-corrosive Mg(OH)2 solution. Hydrogen evolution becomes more intensive as polarization potential increases, particularly when the potential at the film-covered Mg surface is close to or more positive than the hydrogen equilibrium potential, suggesting that an "anodic hydrogen evolution" (AHE) reaction occurs on the substrate Mg in film pores, and the significantly intensified AHE causes film rupture at high potential.
| Original language | English |
|---|---|
| Pages (from-to) | 758-765 |
| Number of pages | 8 |
| Journal | Corrosion Science |
| Volume | 98 |
| DOIs | |
| State | Published - Sep 1 2015 |
Bibliographical note
Publisher Copyright:© 2015 Elsevier Ltd.
Funding
The research was sponsored by the U.S. DOE EERE Vehicle Technologies Office . This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The authors thank Dr. M.P. Brady, Dr. Jeffery K. Thomson and Dr. Bruce A. Pint for providing beneficial discussion and useful comments. Ms. T. Lowe's help in SEM and Ms. S. Curlin's assistance in optical microscopy are appreciated.
| Funders | Funder number |
|---|---|
| U.S. DOE EERE |
Keywords
- A. Magnesium
- B. EIS
- B. SEM
- B. TEM
- C. Anodic dissolution
- C. Negative difference effect
