Bioinspired conical copper wire with gradient wettability for continuous and efficient fog collection.

Area of Science:

• Materials Science
• Surface Chemistry
• Water Harvesting Technologies

Background:

• Cactus spines exhibit remarkable efficiency in collecting fog due to their unique surface structures.
• Developing advanced materials for efficient atmospheric water harvesting is crucial for addressing water scarcity.

Purpose of the Study:

• To fabricate conical copper wires with gradient wettability inspired by cactus spines.
• To evaluate the fog-collection performance of these dual-gradient surfaces.
• To analyze the mechanism behind enhanced fog collection.

Main Methods:

• Fabrication of conical copper wires using gradient electrochemical corrosion.
• Subsequent gradient chemical modification to create tunable wettability.
• Comparative analysis of fog collection efficiency with uniformly wettable surfaces.

Main Results:

• Dual-gradient wettability copper wires demonstrated significantly higher fog-collection ability compared to pure hydrophobic or hydrophilic surfaces.
• The gradient wettability facilitates efficient droplet nucleation, growth, and runoff.
• The underlying mechanism involves synergistic effects of surface topography and wettability gradients.

Conclusions:

• Gradient wettability surfaces are highly effective for enhancing fog collection.
• This biomimetic approach offers a promising strategy for developing efficient atmospheric water harvesting devices.
• Further research can explore scalability and application in arid regions.