Zheng Kaiqiang, Li Shiqing, Chen Zhou, Chen Yunqiang, Hong Yubin, Lan Weiguang
Xiamen University Center for Membrane Application and Advancement, College of Materials, Xiamen University, Xiamen 361005, Fujian, China.
Nanoscale. 2021 Jun 14;13(22):10061-10066. doi: 10.1039/d1nr01823j. Epub 2021 May 27.
Graphene oxide (GO) based membranes are promising for advanced nanofiltration in water treatments but there is a need to improve water flux and membrane stability. Although the interlayer distance of GO membranes can be expanded using intercalants to improve permeability, achieving uniform intercalation without the added complication of water-induced swelling is challenging. Herein, we report the fabrication of GO hybrid lamellar membranes with controllable layer structures to achieve high performance in nanofiltration. The interlayer spacing of the GO hybrid membrane is regulated using TiO intercalants of different sizes, while the stability of GO membranes is enhanced by encapsulating with polyethyleneimine (PEI). The optimal composite membrane delivers a pure water-flux up to 26.0 L m h bar with a 99.9% rejection of methylene blue and eosin under an ultra-low pressure nanofiltration condition. More importantly, the composite membrane sustains good cycling stability after 5 filtration cycles of dye, which enables the potential industrial application in realizing ultra-stable GO based membranes.
基于氧化石墨烯（GO）的膜在水处理中的高级纳滤方面具有广阔前景，但需要提高水通量和膜的稳定性。尽管可以使用插层剂来扩大GO膜的层间距以提高渗透性，但在不增加水致溶胀复杂性的情况下实现均匀插层具有挑战性。在此，我们报道了具有可控层结构的GO杂化层状膜的制备，以实现高性能纳滤。使用不同尺寸的TiO插层剂调节GO杂化膜的层间距，同时通过用聚乙烯亚胺（PEI）封装来增强GO膜的稳定性。在超低压纳滤条件下，最佳复合膜的纯水通量高达26.0 L m h bar，对亚甲基蓝和曙红的截留率为99.9%。更重要的是，复合膜在5次染料过滤循环后仍保持良好的循环稳定性，这使得基于GO的超稳定膜在工业应用中具有潜力。
