Three-Dimensional Double-Layer Multi-Stage Thermal Management Fabric for Solar Desalination.

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m·h under 1 sun (1 kW·m), and 6.26 kg·m·h at a wind speed of 3 m·s. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination.