Enhancing Water Condensation on Hybrid Surfaces by Optimizing Wettability Contrast

Abstract

This study uses a hybrid concept to propose an optimal textured surface morphology for enhancing water condensation. The natural phenomenon-inspired morphology, which combined different degrees of wettability presented on the surface, documented their advantage in water harvesting compared to untreated surfaces. These superiorities might be explained by the appropriate combination of nucleation and water-driven ability facilitated by the superhydrophobic surrounding area. The uniform condensed droplets are effectively agglomerated to achieve the critical size. The best combination was found on a superhydrophobic-hydrophilic hybrid sample that improved water collection efficiency by up to 50% compared to bare Al. Condensation performance also illustrated an interesting tendency that revealed the great contribution of wettability on hydrophilic dots and the water-driven ability of the high-hydrophobicity area. The results were supported by a theoretical model which predicts the critical volume of a single droplet before it has departed from the surface. The findings reveal a good level of agreement between theory and real-time measurement, demonstrating the potential of combinations of hybrid samples to induce water collection efficiency.