Executive Summary : | As the world's population grows, so does the need for water. Conventional techniques of water harvesting, such as desalination, filtration, and groundwater collection, have had some success. Nevertheless, they have significant disadvantages, including low collection efficiency, high energy consumption, and restricted use under specific climatic circumstances. These techniques are being replaced by ones that draw their cues from what nature freely provides and how desert animals thrive in locations where freshwater is scarce. This prompted the investigation of tunable wettability surfaces for use in water harvesting. The substrates like glass, membrane, mesh, and fabric offer a promising solution to address the shortcomings of traditional methods. The aforementioned materials can be modified by adding nanoparticles using hydrothermal, spray pyrolysis, etc. to get the appropriate qualities useful for water harvesting. Creating a Janus substrate that can absorb water by the hydrophilic part and rolling them off to the hydrophobic part is an exciting technique that can increase the amount of water harvested. Potential clogging and fouling of the materials by dust and other particles present in the fog can be addressed by self-cleaning mechanisms under UV and visible light. Developing novel materials with outstanding fog collection efficiency, self-cleaning mechanisms and excellent durability could be a promising approach to fog harvesting technology. |