Fig. 5
Microstructural analysis of porous membranes fabricated from 3D oxidized graphene framework from ref. 37 a Cross-sectional SEM micrograph of graphene-based filter showing micropores. Bottom-left inset shows micrograph of large chunk, while the bottom-right inset shows a zoomed-in image of a part of the same. b SEM micrograph view of a lower dimensional microhole array inside larger microhole structure. Inset on the left shows the front surface of similar such structure. c Large (~10 μm) NaCl crystallites sticking on the membrane after filtration. The inset at the bottom-left shows smaller (<200 nm) NaCl crystals on the surface of membrane. d TEM micrograph of clusters of NaCl nanocrystals on membrane (Images reproduced modified after ref. 37 Article distributed under a Creative Commons CC-BY license)
