Wang Jiali, Gao Xueli, Wang Jian, Wei Yi, Li Zhaokui, Gao Congjie
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education and ‡College of Chemistry and Chemical Engineering, Ocean University of China , Qingdao 266100, China.
ACS Appl Mater Interfaces. 2015 Feb 25;7(7):4381-9. doi: 10.1021/am508903g. Epub 2015 Feb 13.
A novel O-(carboxymethyl)-chitosan (OCMC) nanofiltration (NF) membrane is developed via surface functionalization with graphene oxide (GO) nanosheets to enhance desalting properties. Using ring-opening polymerization between epoxy groups of GO nanosheets and amino groups of OCMC active layer, GO nanosheets are irreversibly bound to the membrane. The OCMC NF membranes surface-functionalized with GO nanosheets are characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, contact angle analyzer, and zeta potential analyzer. The membranes exhibit not only higher permeability but also better salt rejections than the pristine membranes and the commercial NF membranes; besides, the desalting properties are enhanced with the concentration of GO nanosheets increasing. Furthermore, the transport mechanism of GO-OCMC NF membranes reveals that the nanoporous structure of GO-OCMC functional layer and size exclusion and electrostatic repulsion of water nanochannels formed by GO nanosheets lead to the membranes possessing enhanced desalting properties.
通过用氧化石墨烯（GO）纳米片进行表面功能化，制备了一种新型的O-（羧甲基）-壳聚糖（OCMC）纳滤（NF）膜，以增强脱盐性能。利用GO纳米片的环氧基团与OCMC活性层的氨基之间的开环聚合反应，GO纳米片不可逆地结合到膜上。用傅里叶变换红外光谱、X射线光电子能谱、扫描电子显微镜、原子力显微镜、接触角分析仪和zeta电位分析仪对用GO纳米片进行表面功能化的OCMC NF膜进行了表征。与原始膜和商业NF膜相比，这些膜不仅具有更高的渗透率，而且具有更好的脱盐率；此外，随着GO纳米片浓度的增加，脱盐性能增强。此外，GO-OCMC NF膜的传输机制表明，GO-OCMC功能层的纳米多孔结构以及由GO纳米片形成的水纳米通道的尺寸排阻和静电排斥导致膜具有增强的脱盐性能。
