Macroporous foam of reduced graphene oxides prepared by lyophilization

In this study, we demonstrate that water-soluble grafted polymer polyfluorene-grafted-poly(sulfobetainemetahcrylate) (PF-g-PSBMA) allows chemically reduced GO sheets dispersed in aqueous solution due to its ability to stably disperse hydrophobic rGO sheets. Based on the stable rGO/PF-g-PSBMA dispersion, macroporous graphene foam can be simply obtained by lyophilization process (freeze-drying). The resulting composite foam exhibits three-dimensional macroporous structure with high specific surface area and can easily re-dissolve into water. Also, the stable rGO/PF-g-PSBMA dispersion allows solution-based fabrication of thin-film graphene devices. Moreover, PF-g-PSBMA can be removed from rGO foam or film by thermal annealing, and the conductivity of rGO film can be greatly enhanced likely due to its annealing ability.

Figure optionsDownload as PowerPoint slideHighlights
► rGO aqueous dispersion obtained with the assistance of water-soluble polymer PF-g-PSBMA.
► rGO/PF-g-PSBMA foam can be simply obtained by lyophilization process.
► rGO/PF-g-PSBMA foam can re-dissolve into water to fabricate rGO thin-film devices.