Initial stages of water absorption on CeO₂ surfaces at very low temperatures for understanding anti-icing coatings

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. We demonstrate the usefulness of x-ray photoelectron spectroscopy (XPS) as a tool for investigating the anti-icing properties of surfaces simultaneously with their chemical composition by looking at the initial stages of water absorption on the surface of CeO 2 coatings. CeO 2 coatings are robust, hydrophobic, and transmit light, thus they are suitable for a range of applications. In this work, CeO 2 coatings were grown by sputter deposition and transferred to an ultra-high vacuum chamber where they were cooled to ≈ 100 K and exposed to a H 2 O atmosphere at 1 × 10 −8 mbar. XPS measurements were performed before and after the exposure to H 2 O, in-situ and at cryogenic temperatures. The chemical composition of CeO 2 did not change significantly during the experiment. Additionally, XPS revealed that little to no ice formed on the surface of CeO 2 after the H 2 O exposure at ≈ 100 K. In contrast, ice was observed all over the sample holder on which the CeO 2 was mounted. These findings suggest CeO 2 is a promising candidate for future anti-icing coatings and that XPS is a useful technique to investigate the anti-icing properties of surfaces.