Portable water collection bag based on solar-driven interfacial evaporation

Convenient and portable, sustained provision of safe drinking water is crucial for wilderness survival. In this study, a portable water collection bag utilising solar-driven interface evaporation technology has been developed. The water collection bag includes a plastic film, CB-PS microsphere evaporator, and a small vial. By placing on the water surface, the CB-PS microspheres float and absorb sunlight to quickly evaporate the surrounding water. The plastic film and vial make it easy and fast to collect clean and safe drinking water. The device boasts an impressive evaporation rate of 1.64 kg·m⁻²·h⁻¹ under 1 sun illumination. Moreover, the portable water collection bag can withstand harsh acidic and alkaline conditions, efficiently removing organic contaminants from wilderness water sources to meet drinking water standards. Importantly, it is designed for repeated use without any water evaporation rate decreasing. The portable water collection bag also exhibits strong resistance to salt, making it suitable for applications in desalinating seawater into freshwater.