Sustainable solar water purification: Exploring the structural advantages of higher plants

Abstract

Solar vapor generation is a promising technique for water purification, although the development of efficient and sustainable systems for practical use remains challenging. Here, we introduce a higher plant–derived evaporator, leveraging the structural advantages of plants and the synergistic integration of multiple components, including carbon black–coated ultrathin wood slices with perforated pores, nanocellulose aerogel, and vertically aligned wheat straws. This configuration facilitates low-tortuosity water transport within the internal framework while promoting interfacial evaporation at its surface. Under 1 sun, the evaporator achieved an evaporation rate of up to 3.2 kilograms per square meter (kg m−2) per hour. The material’s scalability and the capability to continuously collect clean water in outdoor environments were successfully demonstrated. Outdoors, under a solar intensity of 0.5 to 0.9 sun, the assembled device achieved a daily fresh water yield of up to 10.9 kg m−2 from seawater. With highly accessible renewable raw materials, low production cost, and exceptional water purification efficiency, this cost-effective solar evaporator is edge closer to viable, real-world applications.