Mao Zhengyi, Han Yicheng, Shen Junda, Zhang Lei, Xie Youneng, Liu Jiahua, Wu Haikun, Yu Zhen, Duan Xiaoguang, Zhang Yaoxin, Lu Jian
CityU-Shenzhen Futian Research Institute, Shenzhen, 518045, China.
Department of Mechanical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 0000, China.
Adv Sci (Weinh). 2024 Oct;11(40):e2405639. doi: 10.1002/advs.202405639. Epub 2024 Aug 29.
Solar desalination is a promising solution for alleviating water scarcity due to its low-cost, environmentally friendly, and off-grid capabilities. However, simultaneous salt rejection and heat localization remain challenging, as the rapid salt convection often results in considerable heat loss. Herein, this challenge is overcome via a facile design: i) isolating high-temperature and high-salt zones by rationally designing morning glory-shaped wick structures and ii) bridging high-salt zones and bulk water with low-tortuosity macrochannels across low-temperature surfaces. The salinity gradient in the macrochannels passively triggers convective flow, facilitating the rapid transfer of salt ions from the high-salt zone to the bulk water. Meanwhile, the macrochannels are spatially isolated from the high-temperature zone, preventing heat loss during salt convection and thereby achieving a high evaporation rate (≈3 kg m h) and superior salt rejection even in highly concentrated real seawater. This work provides new insights into salt rejection strategies and advances practical applications for sustainable seawater desalination.
太阳能海水淡化因其低成本、环境友好和离网能力，是缓解水资源短缺的一种很有前景的解决方案。然而，同时实现盐分截留和热量局部化仍然具有挑战性，因为快速的盐分对流往往会导致相当大的热量损失。在此，通过一种简便的设计克服了这一挑战：i）通过合理设计牵牛花形状的毛细结构来隔离高温和高盐区域，以及ii）通过跨越低温表面的低曲折度大通道将高盐区域与大量水体连接起来。大通道中的盐度梯度被动地触发对流，促进盐离子从高盐区域快速转移到大量水体中。同时，大通道在空间上与高温区域隔离，防止盐分对流过程中的热量损失，从而即使在高度浓缩的实际海水中也能实现高蒸发速率（约3 kg m⁻² h⁻¹）和优异的盐分截留。这项工作为盐分截留策略提供了新的见解，并推动了可持续海水淡化的实际应用。
