Graphene Foams: Low‐voltage Driven Graphene Foam Thermoacoustic Speaker (Small 19/2015)

A low-voltage-driven thermoacoustic speaker is fabricated by W. Guo and co-workers using graphene foams synthesized by a chemical vapor deposition method. When an audio signal is applied to the speaker, sound waves are produced due to the periodicity of air vibrations induced by Joule heating. On page 2252, with the feasible tunability in structure and thermoacoustic performance, the graphene foam-based thermoacoustic speaker is shown to be promising for applications requiring flexible or ultrasonic acoustic devices.