Multifunctional flexible membranes based on reduced graphene oxide/tin dioxide nanocomposite and cellulose fibers

Self-standing and flexible membranes based on reduced graphene oxide (rGO)/SnO2 nanocomposite and cellulose fibers are here presented. The flexible membranes are prepared through an easy and eco-friendly protocol: the rGO/SnO2 nanocomposite is synthetized via a microwave-assisted procedure and then assembled with microfibrillated cellulose (MFC) through a water-based process. This process leads to the formation of a nanocomposite in which cellulose nanofibers are integrated with the graphene matrix. Beyond the good flexibility, the nanocomposite membranes present interesting properties in terms of capacitive behavior and catalytic activity: the electrochemical characterizations revealed that such material is an extremely competitive candidate for the oxygen reduction reaction, even comparable to the commonly used Pt-based catalysts. Furthermore, the possible application as electrodes for flexible supercapacitors and piezoresistive sensors is also investigated showing the great potential of such composite material.