Scalable Fabric‐Based Solar Steam Generator

Abstract Solar steam generation has emerged as a promising approach to address water scarcity issues globally. However, a few challenges remain, including high cost, limited scalability, and salt accumulation, before this technique can be adopted by the general population. Here, an all‐in‐one photothermal fabric is reported such as a solar steam generator (SSG), consisting of commercial hydrophilic superfine denier polypropylene fiber and water‐repellent expandable polyethylene foam, manufactured via a conventional weaving machine. By tailoring the yarn twist and density, optimized micro‐macro hierarchical channels can be created in the SSG to provide sufficient water supplementation and continuous steam generation. Due to the Marangoni effect introduced by the temperature gradient along the yarns water with high salinity transports to the bulk water, realizing a salt‐rejecting property. As a result, the SSG demonstrates a rapid evaporation rate of 1.408 kg m⁻² h⁻¹ and energy efficiency of 92.43% under 1 sun, as well as outstanding stability for desalination of high salinity brine (10 wt% NaCl). Furthermore, this strategy provides a new solution to achieve excellent cost‐effectiveness in clean water production at ≈1700 g h⁻¹ $⁻¹. This work provides a sustainable fabric‐based SSG for practical large‐scale clean water production, and can potentially inspire other textiles‐based water treatment.