LAUSR

The fabrication of bendable electronic devices is being a scientific-technological area of very rapid advance in which new materials and fabrication techniques are being continuously developed. In this kind of devices, the fabrication of flexible conductive electrodes adherent to the substrate is a key factor. Besides, eco-friendliness, low cost and fast production are essential requirements for the successful progress of new technologies. In this work, a novel method for obtaining graphene-based flexible electrodes is presented. Conductive films were obtained by means of visible laser irradiation of graphene oxide layers deposited on polyethylene terephthalate substrates besides self-standing membranes sandwiched between glass slides. Despite the low power of the laser system, numerical simulations indicate the development of temperatures over 1000 K throughout the irradiated material. The laser-induced spatially confined heating leads to the reduction of the graphene oxide material whereas the glass-based sandwich assembly avoids reoxidation from surrounding air. By scanning and pixelated modes, reduced graphene oxide electrodes, up to 100 μm in thickness, and with conductivities as low as 6×10-4Ωm were obtained in an easy and versatile way. Proof-of-concept microsupercapacitors and electrochemical sensors were fabricated with this technique, showing promising performance.