Twisted integration of high-efficiency photothermal/water-transported yarns for boosting solar-powered fabric evaporator

Positioned as high-efficiency low-cost desalination technology, solar interfacial vapor generation still remains challenging in precisely managing interfacial photothermal behaviors. Here, an integral solar-heating yarn twisted by both carbon nanotube (CNT) fibers and cotton yarns processed via carbon black slurry is developed for architecting high-efficiency fabric evaporators, where modified CNT and cotton serve as the solar-heating unit and water-supply unit, respectively. The unique structure of hybrid yarns features pronounced gradient photothermal difference of 5 °C between CNT and cotton regions in dry state, and meanwhile enables robust Marangoni vapor flows and weak hydration state. As a result, the crafted fabric evaporator has a superior evaporation rate of 2.83 kg m−2 h−1, which is the highest value reported among 2D fabric evaporators. This work introduces an innovative strategy for high-efficiency interfacial solar heating, significantly boosting evaporation performance of flexible and portable evaporators.