Scanning droplet adhesion microscopy
We have invented Scanning Droplet Adhesion Microscopy (SDAM) to measure the fine wetting details of water-repellent surfaces. SDAM does not require a direct line of sight of the contact area, allowing measurement of uneven surfaces such as fabrics or biological surfaces. It is extremely sensitive and 1000 times more precise than the previous wetting characterization methods. In addition, it can detect wetting properties of microscopic functional features that were previously very difficult to measure. The method has been applied in the characterization of novel materials, including robust superhydrophobic surfaces, superoleophobic slippery lubricant-infused surfaces, 3D printed superhydrophobic structures, and various commercial superhydrophobic coatings.
Selected publications:
- Liimatainen, V., Vuckovac, M., Jokinen, V., Sariola, V., Hokkanen, M., Zhou, Q., Ras, R.H.A., “Mapping microscale wetting variations on biological and synthetic water repellent surfaces”, Nature Communications, 8, 1798, 2017.
- Wang, D., Sun, Q., Hokkanen, M.J., Zhang, C., Lin, F.Y., Liu, Q., Zhu, S.P., Zhou, T., Chang, Q., He, B. Zhou, Q., Chen., L, Ras, R., Deng, X., “Design of robust superhydrophobic surfaces", Nature, 582(7810), pp.55-59, 2020.
- Hokkanen M.J., Backholm M., Vuckovac, M., Zhou, Q., Ras R.H.A., “Force-based wetting characterization of stochastic superhydrophobic coatings at nanonewton sensitivity”, Advanced Materials, 2105130, 2021.
- Dong, Z., Schumann, M.F., Hokkanen, M.J., Chang, B., Welle, A., Zhou, Q., Ras, R.A.H., Xu, Z., Wegener, M., and Levkin, P.A., “Superoleophobic Slippery Lubricant-Infused Surface: Combining Two Extremes in the Same Surface”, Advanced Materials, 1803890, 2018.
- Dong, Z., Vuckovac, M., Cui, W., Zhou, Q., Ras, R.H. and Levkin, P.A., "3D printing of superhydrophobic objects with bulk nanostructure", Advanced Materials, 33(45), p.2106068, 2021.