Water harvesting through the condensation of vapor in air has the potential to alleviate water scarcity in arid regions around the globe. When water vapor is condensed on a cooled surface, tiny water droplets act as thermal barriers. Thus, they must be removed rapidly for efficient water harvesting. Passive technologies for droplet removal rely on in-site growth and direct contact of densely distributed droplets. However, it is challenging to remove submicrometer droplets that lead to a poor water harvesting rate. Here, we present a coarsening effect to rapidly remove water droplets with diameters <20 μm from the hydrophilic slippery liquid-infused porous surface (SLIPS). We quantitatively study the driving and drag forces to enhance the rapid droplet size evolution. The self-propelled coarsening effect enables rapid droplet removal regardless of surface orientations, showing a promising approach compared to those on PEGylated hydrophilic surface, hydrophobic SLIPS, and superhydrophobic surface in water harvesting.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Materials Science(all)
- slippery surface
- water harvesting