Robust and Flexible Micropatterned Electrodes and Micro-Supercapacitors in Graphene-Silk Biopapers

Robust and flexible micro-supercapacitors based upon a graphene oxide-silk layered bionanocomposite is reported. Generation of micropatterned electrodes with sub-micrometer spatial resolution is accomplished using a novel resist-stenciling technique, enabling the transfer of complex microcircuit designs to a graphene oxide-silk layered substrate as chemically reduced features microfeatures across wafer-length scales. Resist-stenciling can produce micropatterned reduction features with over ten times the feature density compared to techniques such as laser-scribing or screen printing. As a proof-of-concept, resist-stenciling is used to fabricate the first 2D micro-supercapacitors integrated into a layered graphene bionanocomposite. These demonstrate a specific capacitance of approximate to 128 F g(-1), good capacitance retention under charge cycling (87.5% after 2000 cycles), and repeated mechanical bending without failure. Resist-stenciling leverages tools currently in use by the microelectronics industry to enable the scalable, high-resolution conversion of layered nanocomposites into microelectronic circuit, storage, and sensing elements.