Zhao Zhifang, Wang Jiankai, Yu Shaoxuan, Qi Zhaorui, Sun Zhuangzhi, Zhang Xingli
College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin 150040, China.
ACS Appl Mater Interfaces. 2024 Sep 11;16(36):48470-48480. doi: 10.1021/acsami.4c08345. Epub 2024 Aug 26.
Solar-driven interfacial evaporation technology is a novel and efficient desalination process that helps alleviate the global shortage of freshwater resources. We developed a Janus evaporator assembled from cotton hydrogel, hydrophilic polyester fabric (PF), and Hydrophobic Wood (PW). By doping graphene oxide and TiO as light-absorbing materials within the hydrogel, we achieved a high absorptivity of over 90% across the entire solar spectrum. The hydrophilically modified PF, combined with the PW substrate, provided robust water transport and reduced thermal losses. Subsequent optical path simulations using TracePro74 software verified that the sawtooth light-trapping design of the wood substrate increased multiple light reflections and absorption (compared to a flat structure), enhancing light absorption capabilities. The sawtooth interface also enlarged the evaporation area, further boosting evaporation performance. The cleverly designed evaporator exhibited an evaporation rate of 1.722 kg m h and an efficiency of 83.1% under 1 sun irradiation. Additionally, after applying polydimethylsiloxane to the single surface of the photothermal hydrogel for low surface energy treatment, the resulting Janus structure demonstrated asymmetric wettability that prevented salt ions from accumulating on the irradiated interface. After 8 h of continuous evaporation in saline water (10 wt %), only slight salt crystallization occurred at the edges. The evaporator maintained long-term stability during a 15 day cyclic test, and the produced freshwater fully met the relevant drinking water standards. The components of the evaporator are characterized by simple fabrication, low cost, and eco-friendliness, offering significant application potential in the global context of energy conservation and emission reduction initiatives.
太阳能驱动的界面蒸发技术是一种新型高效的海水淡化工艺，有助于缓解全球淡水资源短缺问题。我们开发了一种由棉水凝胶、亲水性聚酯织物（PF）和疏水性木材（PW）组装而成的Janus蒸发器。通过在水凝胶中掺杂氧化石墨烯和TiO作为光吸收材料，我们在整个太阳光谱范围内实现了超过90%的高吸收率。亲水性改性的PF与PW基材相结合，提供了强大的水传输能力并减少了热损失。随后使用TracePro74软件进行的光路模拟验证了木材基材的锯齿形光捕获设计增加了多次光反射和吸收（与平面结构相比），增强了光吸收能力。锯齿形界面还扩大了蒸发面积，进一步提高了蒸发性能。精心设计的蒸发器在1个太阳辐照下的蒸发速率为1.722 kg m h，效率为83.1%。此外，在光热水凝胶的单面涂覆聚二甲基硅氧烷进行低表面能处理后，所得的Janus结构表现出不对称润湿性，可防止盐离子在辐照界面上积累。在盐水（10 wt%）中连续蒸发8小时后，仅在边缘出现轻微的盐结晶。蒸发器在15天的循环测试中保持长期稳定性，产生的淡水完全符合相关饮用水标准。该蒸发器的组件具有制造简单、成本低和环保的特点，在全球节能减排倡议背景下具有巨大的应用潜力。
