Effect of deposition pattern of water on fog-harvesting performance of Janus mesh

The effect of different deposition patterns of water on the fog-harvesting performance of Janus meshes is investigated with a systematic adjustment of mesh geometry for four different Janus configurations. In the present work, a dropwise deposition pattern of water is observed to deteriorate fog-harvesting yield by locally disturbing fog flow around a water drop, which weakens impact inertia of fog particles. A super-hydrophilic mesh surface, on the other hand, provides the most aerodynamically favorable environment via filmwise deposition of water. Besides these effects from local aerodynamics, water transport across Janus mesh via wettability gradient is also found to be an important factor determining fog-harvesting yield by influencing drainage efficiency. Water drainage can be maximized when the directions of fog flow and wettability gradient of Janus mesh are both the same, which is suitable for transporting water via air flow.