Gu Qilin, Albert Ng Tze Chiang, Sun Qiaomei, Kotb Elshahawy Abdelnaby Mohamed, Lyu Zhiyang, He Zeming, Zhang Lei, Ng How Yong, Zeng Kaiyang, Wang John
Department of Materials Science and Engineering, National University of Singapore 117574 Singapore
Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore 1 Engineering Drive 2 117576 Singapore.
RSC Adv. 2019 Jan 11;9(3):1591-1601. doi: 10.1039/c8ra08758j. eCollection 2019 Jan 9.
Although different metal-organic framework (MOF) membranes have been widely studied for gas separation, their application for water treatment is still in its infancy. MOF membranes with improved hydrophilicity and stability are particularly essential for water/wastewater treatment. Herein, we have successfully developed heterogeneous membranes (Zn/Co-ZIF-L) composed of vertically standing leaf-like crystals of Zn-ZIF-L grown onto porous ceramic supports, followed by the subsequent heterogeneous growth of Co-ZIF-L. The heterogeneous membranes show improved hydrophilicity (WCA = 13.6 ± 1.6°) and enhanced anti-bacterial adhesion. Significantly, they simultaneously deliver a relative high water flux and much improved anti-bacterial adhesion when compared with the homogeneous membranes (Co-ZIF-L and Zn-ZIF-L). The improvements are attributed to the intrinsic hydrophilic nature of Co-ZIF-L, their epitaxial growth onto Zn-ZIF-L as well as the increased surface roughness. The success of constructing a heterogeneous MOF structure shows an effective strategy to achieve the hydrophilic MOF membranes with considerably enhanced stability for water treatment.
尽管不同的金属有机框架（MOF）膜已被广泛研究用于气体分离，但其在水处理方面的应用仍处于起步阶段。具有改善的亲水性和稳定性的MOF膜对于水/废水处理尤为重要。在此，我们成功开发了由垂直生长在多孔陶瓷载体上的Zn-ZIF-L叶状晶体组成的异质膜（Zn/Co-ZIF-L），随后进行Co-ZIF-L的异质生长。该异质膜表现出改善的亲水性（水接触角WCA = 13.6 ± 1.6°）和增强的抗菌粘附性。值得注意的是，与均质膜（Co-ZIF-L和Zn-ZIF-L）相比，它们同时具有相对较高的水通量和大大改善的抗菌粘附性。这些改进归因于Co-ZIF-L的固有亲水性、它们在Zn-ZIF-L上的外延生长以及表面粗糙度的增加。构建异质MOF结构的成功展示了一种有效的策略，可实现具有显著增强的稳定性的亲水性MOF膜用于水处理。
