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arXiv · 2311.04639

Initial Stages of Water Absorption on $\mathbf{CeO}_{2}$ Surfaces at Very Low Temperatures for Understanding Anti-Icing Coatings

Anna Cecilie Åsland·Simon P. Cooil·Damir Mamedov·Håkon I. Røst·Johannes Bakkelund·Zheshen Li·Smagul Karazhanov·Justin W. Wells
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Abstract

Anti-icing coatings are intended to prevent ice formation on surfaces, minimising the risk of surface-related damage and also reducing ice-related hazards in society. $\mathrm{CeO}_{2}$ coatings are robust, hydrophobic, and transmit light, thus they are suitable for a range of applications. However, their evolving surface chemistry during the initial stages of $\mathrm{H}_{2}\mathrm{O}$ exposure at very low temperatures has not been investigated, despite that this is important for understanding their anti-icing properties. To study this, $\mathrm{CeO}_{2}$ coatings were grown by sputter deposition, cooled to $\approx100\,$K and exposed to a $\mathrm{H}_{2}\mathrm{O}$ atmosphere at $1\times10^{-8}\,\mathrm{mbar}$. We demonstrate the usefulness of X-ray photoelectron spectroscopy (XPS) as a tool for investigating the anti-icing properties of surfaces. We present XPS measurements of $\mathrm{CeO}_{2}$ coatings before and after exposure to $\mathrm{H}_{2}\mathrm{O}$, in-situ and at cryogenic temperatures. XPS reveals that little to no ice forms on the surface of $\mathrm{CeO}_{2}$ after the $\mathrm{H}_{2}\mathrm{O}$ exposure at $\approx100\,$K. In contrast, ice was observed all over the sample holder on which the $\mathrm{CeO}_{2}$ was mounted. These findings suggest that $\mathrm{CeO}_{2}$ is a promising candidate for future anti-icing coatings.

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Anna Cecilie Åsland, Simon P. Cooil, Damir Mamedov, Håkon I. Røst, Johannes Bakkelund, Zheshen Li, Smagul Karazhanov, Justin W. Wells. 2024-05-10. Initial Stages of Water Absorption on $\mathbf{CeO}_{2}$ Surfaces at Very Low Temperatures for Understanding Anti-Icing Coatings. https://doi.org/10.1088/2053-1591%2Fad913e

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