Testing the performance of superhydrophobic aluminum surfaces

F Javier Montes Ruiz-Cabello; Pablo F Ibáñez-Ibáñez; J Francisco Gómez-Lopera; José Martínez-Aroza; Miguel Cabrerizo-Vílchez; Miguel A Rodríguez-Valverde

doi:10.1016/j.jcis.2017.08.032

Testing the performance of superhydrophobic aluminum surfaces

J Colloid Interface Sci. 2017 Dec 15:508:129-136. doi: 10.1016/j.jcis.2017.08.032. Epub 2017 Aug 12.

Authors

F Javier Montes Ruiz-Cabello¹, Pablo F Ibáñez-Ibáñez², J Francisco Gómez-Lopera³, José Martínez-Aroza⁴, Miguel Cabrerizo-Vílchez², Miguel A Rodríguez-Valverde²

Affiliations

¹ Biocolloid and Fluid Physics Group, Applied Physics Department, Faculty of Sciences, University of Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain. Electronic address: fjmontes@ugr.es.
² Biocolloid and Fluid Physics Group, Applied Physics Department, Faculty of Sciences, University of Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain.
³ Applied Physics Department, Faculty of Sciences, University of Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain.
⁴ Applied Mathematics Department, Faculty of Sciences, University of Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain.

PMID: 28822862
DOI: 10.1016/j.jcis.2017.08.032

Abstract

The analysis of wetting properties of superhydrophobic surfaces may be a difficult task due to the restless behavior of drops on this type of surfaces and the limitations of goniometry for high contact angles. A method to validate the performance of superhydrophobic surfaces, rather than standard goniometry, is required. In this work, we used bouncing drop dynamics as a useful tool to predict the water repellency of different superhydrophobic surfaces. From bouncing drop experiments conducted over a wide range of superhydrophobic surfaces, we found that those surfaces with a proper roughness degree and homogeneous chemical composition showed higher water-repellency. We also conducted a drop condensation study at saturating conditions aimed to determine whether there is direct correlation between water repellency and condensation delay. We found that the drop condensation process is strongly related to the surface topography, as well as the intrinsic wettability. The condensation is promoted on rough surfaces but it is delayed on intrinsically hydrophobic surfaces. However, the differences found in condensation delay between the superhydrophobic surfaces explored in this study cannot be justified by their chemical homogeneity nor their efficiency as water repellent surfaces, separately.

Keywords: Bouncing drop; Condensation delay; Superhydrophobic aluminum surfaces.