Chen Kai, Han Shijie, Zhang Shangsheng, Du Hongmei, Zhang Zhengzhi, Wang Jian, Luo Xunkai, Li Yulian
School of Mechanical and Electrical Engineering, China University of Mining and Technology (Beijing) 100083 Beijing China
School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing) 100083 Beijing China.
RSC Adv. 2025 Apr 1;15(12):9546-9554. doi: 10.1039/d4ra08736d. eCollection 2025 Mar 21.
Atmospheric water harvesting (AWH) technology is widely regarded as a promising technology to solve the problem of fresh water shortage. Hygroscopic salt-hydrogel composites have attracted extensive attention due to their high hygroscopic salt-carrying capacity. However, their complex preparation process, salting-out and low water collection efficiency restrict their development. In this study, we prepared calcium alginate (CA) and [2-(methylpropoxy) ethyl dimethyl-(3-propyl sulfonic acid)ammonium hydroxide (PDMAPS)] double-network-structured hydrogel microspheres using a novel drip-free polymerization method. Then, a CA/PDMAPS/CNT/LiCl composite adsorbent was prepared by adding carbon nanotubes (CNTs) and LiCl. The preparation process was simple and suitable for mass production. Zwitterionic groups in the double-network structure (cationic -N(CH) and anionic -SO ) could produce electrostatic effects with Li and Cl, thereby binding LiCl and solving the traditional salting-out problem. A binary salt system could also be formed, which greatly enhanced water-collection capacity. At 22 °C with RH = 90%, the maximum water collection of the hydrogel microspheres was 3.586 g g. Compared with single-network-structured hydrogels, the reported system exhibited an enhancement of 434% in its water collection efficiency. Under natural light, it desorbed more than 80% of the adsorbed water in 3-4 h. In summary, the dual-network-structured hydrogel microspheres represent a promising material for atmospheric water collection.
大气取水（AWH）技术被广泛认为是解决淡水短缺问题的一项很有前景的技术。吸湿盐-水凝胶复合材料因其高吸湿载盐能力而备受关注。然而，其复杂的制备过程、盐析现象和低集水效率限制了它们的发展。在本研究中，我们采用一种新型的无滴聚合法制备了海藻酸钙（CA）和[2-(甲基丙氧基)乙基二甲基-(3-丙基磺酸)氢氧化铵（PDMAPS）]双网络结构的水凝胶微球。然后，通过添加碳纳米管（CNT）和LiCl制备了CA/PDMAPS/CNT/LiCl复合吸附剂。制备过程简单且适合大规模生产。双网络结构中的两性离子基团（阳离子-N(CH) 和阴离子-SO ）可与Li 和Cl 产生静电作用，从而结合LiCl并解决传统的盐析问题。还可形成二元盐体系，大大提高了集水能力。在22℃、相对湿度为90%的条件下，水凝胶微球的最大集水量为3.586 g/g。与单网络结构的水凝胶相比，该体系的集水效率提高了434%。在自然光下，它能在3-4小时内解吸出80%以上吸附的水分。综上所述，双网络结构的水凝胶微球是一种很有前景的大气取水材料。
