We describe the fabrication and characterization of Near-Field Communication (NFC) devices based on highly flexible, carbon-based antennas composed of stacked graphene multilayers. This material features a high value of conductivity (4.20?*?105?S/m) comparable to monocrystalline graphite, but is much more flexible and processable. We first studied the replacement of metal with carbon antennas using computer modeling, to select the best design. Then we manufactured several devices to be used according to the communication protocol ISO/IEC 15693. The inductance of the G-paper antennas was tested before and after hundreds of thousands of bending cycles at bending radii of 45 and 90?mm. During bending the self-resonance frequency and inductance peak showed minimal variation and the resistance at 1?MHz changed from 33.09?O to 34.18?O, outperforming standard, commercial metallic antennas. The devices were successfully tested by exchanging data with a smartphone and other commercial NFC readers, matching the performance of standard, commercial metallic antennas. The graphene antennas could be deposited on different standard polymeric substrates or on textiles. Smart cards, flexible NFC tags and wearable NFC bracelets were prepared in this way to be used in electronic keys, business cards and other typical NFC applications.

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DOI: 10.1016/j.mattod.2018.01.007