Graphene foam resonators: Fabrication and characterization

Three-dimensional graphene foams (GFs) benefit from a large surface area and unique physical properties. We present here the first-ever miniaturized GF-based resonators. We developed a simple yet reliable fabrication process, in which GFs are synthesized and assembled on a cavity to form suspended GF devices. We electrostatically excited these devices and analyzed their resonance and ring-down responses. We observed significant energy dissipation, as the quality factor of the devices was in the order of several tens. Additionally, we investigated the influence of temperature on the operation of the devices and found that high temperatures mechanically soften the resonators but also considerably enhance energy dissipation. Finally, our devices demonstrated a mode-coupling of a resonance mode and a mode having twice its frequency. Thus, this work paves the way toward the development of novel GF resonators that could be integrated into future devices, such as GF-based nano-electromechanical sensors, electrical circuits, and oscillators.