Abstract

The rapid development of micro-electro-mechanical systems working in tight and small spaces in the aerospace, precision instruments, materials, bio-medical and other fields intensively stimulated the urgent demand for high-performance miniaturized energy storage devices. Micro-supercapacitors are newly-developed promising miniaturized high-power micro-electrochemical energy storage devices for on-chip uses which are directly compatible with these micro-systems. Currently, graphene-based 2D materials have been demonstrated as very attractive electrode materials for micro-supercapacitors taking advantage of the unique features of graphene and planar device geometry. This review summarizes the latest advances of graphene-based planar micro-supercapacitors, including the device development, different graphene-based materials (graphene sheets, graphene quantum dots, activated graphene, graphene/carbon nanotube, graphene/metal oxide, graphene/polymer), microfabrication strategies of micro-electrode and devices (photolithography techniques, electrochemical methods, laser writing, etc.), electrolyte (aqueous, organic, ionic, and gel), device configuration (symmetric and asymmetric). Lastly, the perspectives and possible future development directions of graphene-based micro-supercapacitors are shortly discussed.