Sharif Digital Repository

In this study, graphene oxide fibers are introduced as new graphene oxide (GO) membranes with the capability of ion selectivity. Graphene oxide fibers, like other macro structured membranes, are always associated with cavities and defects. To solve this problem, a 50% combination of graphene oxide suspension including small sheets with an average size of ~ 0.5 µm2 and large sheets with an area of more than 10 µm2 was used. According to the morphological results of scanning electron microscopy, as well as the amount of ionic transport through the fiber, reduction of cavities and its defects were confirmed. Moreover, it was found that ionic current through fibers consist of large and small GO... 

Nanostructured graphene based membranes demonstrated excellent capabilities in various applications in nanofiltration and energy conversion due to unique atomically smooth surfaces and adjustable pore size or interlayers spacing at Angstrom scales. There are some reports on the osmotic power generation using physical confinements and electrostatic interactions between ions and GO membranes. However, the results indicated insufficient power densities (˂1 W/m2) can be achieved because of swelling of interlayer spacing of the GO membranes upon exposure to aqueous solutions which results in reducing the influence of confinement on ionic motilities. Here, the GO fibers is presented as one...