Bioinspired Janus Evaporator for Efficient Desalination of Saline‐Alkali and Seawater Through Photothermal‐Capillary Effects

Soil salinization and freshwater scarcity are critical constraints on sustainable agriculture. Inspired by the salt‐resistance mechanisms of Tamarix chinensis , this study combined textile technology to ingeniously integrate a hydrophobic PP/MXene photothermal sheath with a hydrophilic cotton core into functionalized yarns, successfully developing a Janus core‐sheath evaporator (PM‐CSY‐F). MXene is uniformly dispersed within the polypropylene matrix, significantly enhancing internal multiple light scattering and interlayer reflections, thereby improving the photothermal conversion efficiency. By precisely regulating the number of cotton cores, the water transport rate can be accurately controlled, achieving synergistic optimization of efficient solar absorption and capillary‐driven rapid water transport. The sheath and nighttime radiative cooling enable self‐cleaning and suppress salt accumulation. The PP matrix isolates MXene from highly alkaline water, improving stability. Under 1 kW m −2 irradiation, the evaporator achieved a 2.34 kg m −2 h −1 evaporation rate for saline‐alkali water (150 m Na + ). In simulated seawater, performance improved to 2.46 kg m −2 h −1 . Outdoor tests yielded 12.99 kg m −2 of water over 8 h. The textile‐based design supports scalable manufacturing. This approach provided a viable solution for both soil remediation and freshwater generation, advancing sustainable agriculture in vulnerable regions.