The first body of the work in this project was dedicated to the optimization of experimental conditions in “scanning probe” technique for the investigation of local activities of corroding interfaces. Active metal dissolution during electrochemical probing compromised the reproducibility of the “scanning probe” technique. We discovered that the environment plays a crucial role in the stability of the measurement. In particular, application of a hydrophobic oil on metal interface or oxygen removal can significantly improve the experimental conditions. These allowed the use of “scanning probe” techniques to reveal activities of single grains on polycrystalline iron and zinc. All measurements were complemented with computational quantum mechanical modelling and successfully rationalized using computed free adsorption and dissolution energies. These works were disseminated via publication:
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.
