Ever since it was discovered, researchers have been thinking of more and more applications for graphene, with a heavy focus on electrical and optical systems. This is because the material has many useful electrical and optical properties, but it also has beneficial mechanical properties. Now researchers at the University of Belgrade, Serbia, as reported by the Institute of Physics, have successfully used graphene in a microphone.

Graphene is an atom-thick sheet of carbon that is transparent, flexible, strong, and highly conductive. Its high strength and flexibility is what the researchers are taking advantage of, along with its light weight, by making an acoustic membrane out of it. This is the part of a condenser microphone that actually converts sound into an electrical current. The membrane is about 60 layers of graphene thick and the researchers placed it into the housing of a commercial microphone for testing. Compared to a typical nickel-based microphone, the graphene-based version demonstrated a 15 dB higher sensitivity at frequencies up to 11 kHz. In theory adding more layers to the membrane will allow it to perform well in the ultrasonic range of the spectrum.

While it is impressive as is, the graphene-based microphone is just a proof of concept, especially as graphene is difficult to produce. As manufacturing obstacles are knocked down though, we could see these more sensitive microphones appearing at lower costs.

Source: Institute of Physics