Colloidal methods for the fabrication of Mn3O4-graphene film and bulk supercapacitors

Composite Mn3O4-graphene electrodes are fabricated by different colloidal processing methods, such as screen printing (SP), electrophoretic deposition (EPD) and slurry impregnation (SI) for energy storage in thin film and bulk supercapacitors (SCs). Good capacitive behavior of electrodes is linked to beneficial effect of current collectors and advanced colloidal processing. The results presented stress the importance of poly[1-[4-(3-carboxy-4-hydroxyphenylazo) benzenesulfonamido]-1,2-ethanediyl, sodium salt] (PAZO), which is used as a versatile co-dispersing, charging, binding and film forming agent for Mn3O4 and graphene. The effect of PAZO is linked to aromatic structure of its chelating monomers, which facilitate the fabrication of advanced inks for SP, suspensions for EPD and concentrated slurries for SI. Good capacitive behavior of thin film and bulk electrodes is achieved at low impedance. The properties of the SC electrodes make them promising for energy storage.