Periodic Reporting for period 1 - NELMA (Nanoscale Electrochemistry on Light Metallic Alloys)
Reporting period: 2018-06-01 to 2020-05-31
The main limitation for the widespread use of these materials remains the unknown mechanisms of their degradation and, as a result, absence of effective strategies of corrosion protection. It is known that light metal alloys are nanostructured to expose particular surface sites, but probing the intrinsic activity of these sites is usually beyond current experimental capability. In this project, we present a new tool that makes use of a special probe (known as “scanning probe”) to measure the functional properties of light metal alloys in minute detail in order to guide the development of more durable materials.
In essence, we developed and implemented a range of “scanning probe” techniques to measure functional (electrochemical) information during metal dissolution with unprecedented spatial resolution, which is broadly relevant for corrosion applications. We effectively showed that this novel approach is generally applicable to the degradation of polycrystalline metals by applying it to study the corrosion of zinc and iron. In addition, we adapted the “scanning probe” technology to explore local properties of the double layer on metal interfaces, thereby complementing the toolbox of local electrochemical methods for materials characterization.
L. C. Yule et al., “Nanoscale Active Sites for the Hydrogen Evolution Reaction on Low Carbon Steel”, The Journal of Physical Chemistry C, 2019, 123 (39), 24146-24155.
L. C. Yule et al., “Nanoscale electrochemical visualization of grain-dependent anodic iron dissolution from low carbon steel”, Electrochimica Acta, 2020, 332, 135267.
V. Shkirskiy et al., “Scanning Electrochemical Cell Microscopy and Correlative Surface Structural Analysis to Map Anodic and Cathodic Reactions on Polycrystalline Zn in Acid Media”, Journal of The Electrochemical Society, 2020, 167 (4), 041507
The latter study produced a lot of interest, with presentation given on international conference dedicated to corrosion “Eurocorr2019” (Seville, Spain).
After completing these works, significant focus was given to further development of “scanning probe” techniques, specifically to the investigation of properties of double layer on metal interfaces. This allowed us to interrogate minute structural features of double layer of gold nanoparticles. This work was disseminated via publication:
V. Shkirskiy et al., “Nanoscale Electrochemical Impedance Measurements in Scanning Ion Conductance Microscopy”, submitted to ACS Analytical Chemistry.
Over the project period, one review article was published addressing various aspects of the use of the “scanning probe”:
C. L. Bentley et al., “Nanoscale electrochemical mapping”, ACS Analytical Chemistry, 2018, 91 (1), 84-108.
In summary, this project led to the development of novel methodologies for probing metal interfaces. The “scanning probe” techniques have been used to investigate a range of phenomena in corrosion complemented with quantum mechanical modeling.