Chen Si, Zheng Zhiheng, Liu Huan, Wang Xiaodong
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
ACS Appl Mater Interfaces. 2023 Apr 5;15(13):16640-16653. doi: 10.1021/acsami.2c21298. Epub 2023 Mar 23.
Solar-powered interfacial evaporation has been recognized to be a promising and sustainable technology for seawater desalination, in view of the challenge of freshwater scarcity and fossil energy storage. Nevertheless, current cutting-edge interfacial evaporation systems mostly ignore the issues of intermittent solar irradiation and bacterial contamination. We have hereby developed a novel type of an interfacial evaporator equipped with carbon black (CB)/chitosan (CS)-decorated phase-change microcapsules as a multifunctional photothermal material for solar-powered seawater desalination, based on a highly efficient, antibacterial, and salt-resistant multipurpose strategy. In the developed microcapsules, an -docosane phase-change material (PCM) core was engulfed in a TiO shell, followed by surface decorating a CB/CS nanocomposite layer. A high thermal energy-storage capacity of more than 140 J g was achieved, thanks to tight sealing of -docosane as a PCM core in the perfect core-shell structured microcapsules. Moreover, a rational combination of CS and CB nanoparticles not only contributes an extremely high solar absorption efficiency of 95.04% and good wettability to the as-synthesized microcapsules, but also imparts outstanding antibacterial and salt-resistant abilities to them. These innovative designs enable the developed evaporator to gain a high evaporation rate of 2.58 kg m h, along with an evaporation efficiency higher than 90% for consecutive and stable evaporation of seawater under intermittent solar illumination. Compared to conventional evaporators without a PCM, there is an increase by 1.03 kg m in the total water production of the develop evaporator under natural solar illumination for 8 h on a semicloudy day. The resultant evaporated water presents good vegetation compatibility to meet the requirement of crop growth for agricultural cultivation. This work provides a new pathway for designing and developing the high-performance interfacial evaporators with prominent antibacterial and salt-resistant abilities to produce purified water through solar-powered sustainable seawater desalination.
鉴于淡水短缺和化石能源储存的挑战，太阳能驱动的界面蒸发已被认为是一种有前途的可持续海水淡化技术。然而，目前的前沿界面蒸发系统大多忽视了间歇性太阳辐射和细菌污染问题。在此，我们基于高效、抗菌和耐盐的多用途策略，开发了一种新型界面蒸发器，该蒸发器配备了炭黑（CB）/壳聚糖（CS）修饰的相变微胶囊作为太阳能驱动海水淡化的多功能光热材料。在所开发的微胶囊中，正二十二烷相变材料（PCM）核被包裹在TiO壳中，随后在表面修饰CB/CS纳米复合层。由于正二十二烷作为PCM核被紧密密封在完美的核壳结构微胶囊中，实现了超过140 J g的高热能存储容量。此外，CS和CB纳米颗粒的合理组合不仅为合成的微胶囊带来了95.04%的极高太阳能吸收效率和良好的润湿性，还赋予了它们出色的抗菌和耐盐能力。这些创新设计使所开发的蒸发器能够获得2.58 kg m h的高蒸发速率，并且在间歇性太阳光照下连续稳定蒸发海水时蒸发效率高于90%。与没有PCM的传统蒸发器相比，在半阴天自然太阳光照8小时的情况下，所开发的蒸发器总产水量增加了1.03 kg m。所得的蒸发水具有良好的植被兼容性，能够满足农业种植中作物生长的需求。这项工作为设计和开发具有突出抗菌和耐盐能力的高性能界面蒸发器提供了一条新途径，以通过太阳能驱动的可持续海水淡化生产净化水。
