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.

Graphene foam (GF)—a three-dimensional network of hollow graphene branches—is a highly attractive material for diverse applications. However, to date, the heat dissipation characteristics of GFs have not been characterized. To fill this gap, we synthesized GF devices, subjected them to high temperatures, and investigated their thermal behavior by using infrared microthermography. We find that while the convective area of GF devices is comparable to that of bulk materials (such as metals), the coefficient of convection of these devices is several orders of magnitude higher than that of metals. In addition, the GF devices showed a reproducible thermal behavior, which we attribute to negligible temperature-induced morphological changes (as confirmed by Raman analysis). Taken together, our findings suggest GF as a promising candidate material for advanced cooling applications where efficient heat dissipation is needed, e.g., in electrical circuits.