Graphene improves microphone sensitivity by 30 times

Scientists have developed a graphene-based microphone which is nearly 32 times more sensitive than microphones of standard nickel-based construction.

"We wanted to show that graphene, although a relatively new material, has potential for real world applications," said one of the study authors, Marko Spasenovic from the University of Belgrade, Serbia.

"Given its light weight, high mechanical strength and flexibility, graphene just begs to be used as an acoustic membrane material," Spasenovic said.

The researchers created a vibrating membrane - the part of a condenser microphone which converts the sound to a current - from graphene.

The graphene membrane, approximately 60 layers thick, was grown on a nickel foil using chemical vapour deposition, to ensure consistent quality across all the samples.

During membrane production, the nickel foil was etched away and the graphene membrane placed in the same housing as a commercial microphone for comparison.

This showed a 15 decibel higher sensitivity than the commercial microphone.

"The microphone performed as well as we hoped it would," Spasenovic said.

"At this stage there are several obstacles to making cheap graphene, so our microphone should be considered more a proof of concept," he pointed out.

"The industry is working hard to improve graphene production - eventually this should mean we have better microphones at lower cost," Spasenovic noted.

The study was published in the journal 2D Materials.