With documented public water problems in Flint, Mich., and Hoosick Falls, N.Y., caused by corrosion, understanding how copper is affected at the atomic level is critical to avoiding problems in future pipes. Corrosion-related damage costs more than three percent of the United States' Gross Domestic Product (about $503.1 billion, going by 2013 numbers).
Using state-of-the-art in situ microscopy techniques, scientists at Binghamton University were able to watch the oxidation of copper -- the primary building material for millions of miles of water piping -- at the atomic level as it was happening. What they saw could help create pipes with better corrosion resistance.
"Oxidation of metals [the loss of electrons at the molecular or atomic level] is a universal reaction caused by the simple fact that the oxide of most metals is more stable than the metal itself. Resistance to corrosion or oxidation is one of the most important properties for materials exposed to air or water," said Guangwen Zhou, associate professor of mechanical engineering at Binghamton University and co-author on the study.
"Because water is naturally corrosive, especially for pipes carrying hot water, where the elevated temperature accelerates the oxidation/corrosion rates, the Environmental Protection Agency (EPA) requires all water systems monitored for the levels of copper," Zhou added.
"The most common reason for water utilities to add corrosion inhibitors is to avoid copper corrosion. The research findings of our study on the oxidation of copper alloys can facilitate the development of new alloys with improved resistance to corrosion in water."
Beyond water pipes, observing how copper oxidizes also sheds light on maintaining material stability in nanodevices that are used in energy and medical science. Using atomic-resolution electron microscopes, scientists demonstrated that the oxidation of copper occurs via layer-to-island growth of copper oxide on flat copper surfaces with copper atoms evaporating from the surface.
Solid oxide, made of copper and oxygen atoms thermally mixing microscopically above the original surface, is deposited back on the surface. This is different from the long-held idea of a solid-solid transformation. The observation is counterintuitive because if a surface can be made more uneven, it can resist oxidation better.
"Recent advances in instrumentation have made it possible to investigate the oxidation of metals exposed to oxygen gas and elevated temperature with in situ measurements. Employment of these techniques can provide unique opportunities to establish the principles of controlling atomic processes of surface oxidation," Zhou said. "Using these tools, we are able to gain unprecedented insight into the oxidation mechanism of copper and copper alloys."
According to Zhou, not all oxidation is a bad thing. "(Oxidation) can lead to the formation of a protective layer against corrosion attack," he said. "Our results establish the principles of predicting the trend for promoting or suppressing the oxidation of materials, which is much needed for smarter utilization to steer the reaction toward the desired direction for real applications such as corrosion resistance or improved chemical catalysis."
Qing Zhu, Wissam A. Saidi, and Judith C. Yang from the University of Pittsburgh are all co-authors of the study, along with Binghamton graduate student Lianfeng Zou.
The study, "Early and transient stages of Cu oxidation: Atomistic insights from theoretical simulations and in situ experiments" was published in Surface Science.
Guangwen Zhou | EurekAlert!
Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern
20.07.2018 | Princeton University
Relax, just break it
20.07.2018 | DOE/Argonne National Laboratory
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Materials Sciences
20.07.2018 | Physics and Astronomy
20.07.2018 | Materials Sciences