Enhanced fog water harvesting on superhydrophobic steel meshes

Fog water harvesting, inspired by desert organisms, offers a sustainable and low-cost solution to water scarcity, especially in humid coasts. Mesh-based fog collection is gaining research attention due to its passive operation and minimal environmental impact. This study aims to develop effective, low-cost, scalable, and easy-to-apply fog harvester designs while evaluating their performance under fog conditions that closely mimic real-world scenarios. Copper is electrodeposited onto steel meshes to create a rough hydrophobic layer, and modified with a per- and polyfluoroalkyl substances-free silica-sol to reach superhydrophobicity. The modified sample achieves a water harvesting efficiency of 580 mg (cm2h)−1, a 40% improvement over uncoated steel meshes, comparable to the results of single-drop impact studies and fog water harvesting investigations. The key considerations for fog harvesting research, emphasizing the need to calculate fog harvesting efficiency as the ratio of collected water to available atmospheric water generated in experimental setups are highlighted. Without standardized testing protocols, inconsistent results hinder progress and divert focus from real-world applications. To address this, a methodology for a standardized protocol reflecting fog characteristics and environmental conditions is developed. This technological advancement offers a viable strategy to mitigate water scarcity through optimized fog water harvesters based on surface property design and control.