Miniature graphene-based supercapacitors fabricated by laser ablation

Micro-supercapacitors are high-performance energy storage devices, which are particularly important for building a micropower system to power portable and wearable devices. This study demonstrates a fabrication route for graphene-based in-plane micro-supercapacitors using a laser system for micromachining of electrodes on LTCC substrate. Micro-electrodes were patterned by programmed laser scanning. The proposed subtractive fabrication route is green, on demand and it enables the direct printing of micro-scale features (about 50μm) with a precision of 2μm. The width of electrodes was 210μm, spacing between electrodes was 60μm, and the length was 6.8mm. In order to build all solid-state supercapacitive devices, a gel electrolyte was introduced into the active area of micro-electrodes (0.68cm2). Laser patterning enables fabrication of micro-supercapacitors of arbitrary sizes and patterns, thus providing a good opportunity for miniaturized electronic applications. Electrochemical characterization was performed. The resulting micro-supercapacitors deliver an area capacitance of 80.5μF/cm2.