Researchers create graphene speakers for mobile devices

It’s no secret that researchers are considering graphene  a wonder material due to it’s amazing capabilities. The material is making its way into a plethora of products like coatings, sports equipment and even light bulbs. Scientists are constantly looking for ways to maximize its properties and harness them into today’s electronics, and now they’re  one step closer to making graphene audio speakers for mobile devices.

Jung-Woo Choi, Byungjin Cho, Sang Ouk Kim and colleagues at Korea Advanced Institute of Science and Technology (KAIST)  have discovered a simple way to fabricate once-elusive thermoacoustic speakers using the ultra-thin material.

While today’s speakers rely on many mechanical parts that vibrate to create sound and must be encased in an acoustic cavity, this approach complicates manufacturing and limits where listeners can put their speakers.

Scientists have been looking for ways around this by delving into the principle of thermoacoustics, the production of sound by rapidly heating and cooling a material instead of using vibrations. This is all made possible thanks to graphene, which is highly conductive and durable. While some attempts at graphene speakers have succeeded, mass producing them would be a challenge.

So, the KAIST team developed a two-step (freeze-drying and reduction/doping) method for making a sound-emitting graphene aerogel.  The researchers used an array of 16 of aerogels to create a speaker that could operate on 40 Watts of power with a sound quality comparable to that of other graphene-based sound systems.

According to the team, this fabrication method is practical and could even be mass produced for use in mobile devices. Since the speaker is thin and doesn’t vibrate, it could fit snugly against walls and even curved surfaces.

Story and video via American Chemical Society.