Inkjet-printed graphene for flexible micro-supercapacitors

Here we report our multi-institutional effort in exploring inkjet printing, as a scalable manufacturing pathway of fabricating graphene electrodes for flexible micro-supercapacitors. This effort is founded on our recent discovery that graphene oxide nanosheets can be easily inkjet-printed and thermally reduced to produce and pattern graphene electrodes on flexible substrates with a lateral spatial resolution of ~50 μm. The highest specific energy and specific power were measured to be 6.74 Wh/kg and 2.19 kW/kg, respectively. The electrochemical performance of the graphene electrodes compared favorably to that of other graphene-based electrodes fabricated by traditional powder consolidation methods. This paper also outlines our current activities aimed at increasing the capacitance of the printed graphene electrodes and integrating and packaging with other supercapacitor materials.