Xian Weipeng, Xu Xiaoyi, Ge Yongxin, Xing Zhiwei, Lai Zhuozhi, Meng Qing-Wei, Dai Zhifeng, Wang Sai, Chen Ruotian, Huang Ning, Ma Shengqian, Sun Qi
Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China.
State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China.
J Am Chem Soc. 2024 Dec 11;146(49):33973-33982. doi: 10.1021/jacs.4c12829. Epub 2024 Nov 28.
Traditional desalination methods face criticism due to high energy requirements and inadequate trace ion removal, whereas natural light-driven ion pumps offer superior efficiency. Current synthetic systems are constrained by short exciton lifetimes, which limit their ability to generate sufficient electric fields for effective ion pumping. We introduce an innovative approach utilizing covalent-organic framework membranes that enhance light absorption and reduce charge recombination through vertical gradient protonation of imine linkages during acid-catalyzed liquid-liquid interfacial polymerization. This technique creates intralayer and interlayer heterojunctions, facilitating interlayer hybridization and establishing a robust built-in electric field under illumination. These improvements enable the membranes to achieve remarkable ion transport across extreme concentration gradients (2000:1), with a transport rate of approximately 3.2 × 10 ions per second per square centimeter and reduce ion concentrations to parts per billion. This performance significantly surpasses that of conventional reverse osmosis systems, representing a major advancement in solar-powered desalination technology by substantially reducing energy consumption and secondary waste.
传统的海水淡化方法因能源需求高和痕量离子去除不充分而受到批评，而自然光驱动的离子泵效率更高。目前的合成系统受激子寿命短的限制，这限制了它们产生足够电场以有效泵送离子的能力。我们引入了一种创新方法，利用共价有机框架膜，通过在酸催化的液-液界面聚合过程中亚胺键的垂直梯度质子化来增强光吸收并减少电荷复合。该技术形成层内和层间异质结，促进层间杂化并在光照下建立强大的内置电场。这些改进使膜能够在极端浓度梯度（2000:1）下实现显著的离子传输，传输速率约为每秒每平方厘米3.2×10个离子，并将离子浓度降低到十亿分之一。这种性能大大超越了传统反渗透系统，通过大幅降低能源消耗和二次废物，代表了太阳能海水淡化技术的重大进步。
