Synergistic Effect of a Hydrophilic Polymer and Graphene Oxide Laminates

Another reason may be that it changes easily under different feed environments. [ 32 – 34 ] Also, the formation of highly ordered, precise GO laminates through the self-assembly of GO nanosheets is extremely diffi cult. [ 35 ] Some inevitable nonselective defects or out-of-order accumulation will exist in the GO layers due to the repulsive electrostatic interactions caused by negatively charged carboxy groups. [ 14 ] Thus, the separation potential of GO laminates has not been fully explored. Despite these drawbacks, fully utilizing the unique channels of GO laminates could be a simple, feasible, and effective approach to optimizing the transport properties of GO laminates, which are expected to transcend the separation limitations of current state-of-the-art membranes. How can we fully utilize the fast water, gas, or ion transport channels of GO laminates? There are phenomena in nature to be learned. One striking example is that of amphibians (e.g., frogs), whose skin is permeable to water. [ 36,37 ] In order to protect and compensate for their thin and delicate skin, frogs have evolved mucous glands principally distributed on their heads, backs, and tails to produce secretions. By collecting water from the humid environment, these secretions can effectively keep the frog’s skin moist and maintain the frog’s vital activities. This interesting phenomenon inspired us to fabricate a bio-inspired membrane coupling a surface water-capturing layer and GO laminates consisting of water channels. In this bio-inspired membrane, a hydrophilic polymer acts as the surface layer to preferentially capture a large number of water molecules from feed mixtures, resulting in an increase of the driving force across the GO laminates. Finally, the 2D water channels within the interlayers of GO nanosheets would be fully used, realizing fast and selective water permeation through the integrated High-Effi ciency Water-Transport Channels using the Synergistic Effect of a Hydrophilic Polymer and Graphene Oxide Laminates