Researchers at Binghamton University are exploring how Environmental Transmission Electron Microscopy (ETEM) can be leveraged to understand corrosion at an atomic level. Their findings could affect ongoing efforts both in the fields of corrosion resistance and clean energy production.
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The economic burden caused by repairing structures damaged by corrosion is estimated at around $2.5 trillion each year, according to the Institute of Corrosion. Developing methods to prevent or manage rusting could, therefore, have significant practical and economic benefits.
Alongside collaborators from the University of Pittsburgh and the Brookhaven National Laboratory, Professor Guangwen Zhou of Binghamton University has published new research outlining how aberration-corrected environmental electron microscopy (ETEM) can observe surface reactions of samples when exposed to water vapor under realistic pressure and temperature conditions. This allows greater understanding of surface phenomena in technologically relevant conditions.
Although corrosion, or rusting, is well understood across small lengths and time scales in the lab in order to reveal structural properties within an adlayer of condensed water, knowing what happens on an atomic scale under realistic conditions is harder to pinpoint.
The researchers focused on the reactions that occur between water vapor and aluminum in their research, looking for ways to control and prevent them.
The scientists were able to illustrate how water vapor directly induces these transformations of the metal lattice into oxides at room temperature, something that had never before been demonstrated at the atomic scale.
Perhaps the most significant outcome of the research is the discovery of a second layer that occurs underneath the anticipated aluminum hydroxide layer. The TEM clearly showed a crystalline Al(OH)3 outer layer and an Al2O3 amorphous inner layer, making up a passivating bilayer film on the aluminum surface.
This information could have significant implications for efforts to develop corrosion resistance in aluminum as well as other metals.
Dr. Zhou also hopes that studying how the oxygen and hydrogen atoms in water react with metals could create new breakthroughs in clean energy. Aluminum has been suggested for use in hydrogen storage onboard vehicles, and investigating how clean H2 could be produced from the reaction between aluminum and water at ambient temperature could have immense repercussions.
These potential implications have led to sustained investment by the U.S. Department of Energy into Zhou’s work.
References and Further Reading
(No date a) Atomistic mechanisms of water vapor–induced surface passivation - science. Available at: https://www.science.org/doi/10.1126/sciadv.adh5565 (Accessed: 12 December 2023).
Kocher, C. (2023) New research examines corrosion on atomic level - binghamton news, News - Binghamton University. Available at: https://www.binghamton.edu/news/story/4670/how-does-corrosion-happen-new-research-examines-process-on-atomic-level (Accessed: 12 December 2023).
Admin (2021) The effects of corrosion, Institute of Corrosion. Available at: https://www.icorr.org/effects-of-corrosion/#:~:text=Fundamentals%20of%20Corrosion (Accessed: 12 December 2023).