Georgia Tech Institute of Technology researchers have developed Ultrathin Paper Microphone which gets charged from your speech

How about when you run out battery on your smartphone, you shout at it at it gets recharged! Sounds ludicrous right? Researchers from Georgia Tech Institute of Technology have decided to prove you wrong. They have developed a rollable, 125 ?m thin, paper-based triboelectric nanogenerator (TENG) that can harvest energy from your speech and deliver a maximum power density of 121 mW/m2.

The researchers used a laser to zap a grid of microscopic holes in the paper, then coated one side in copper and laid it on top of a thin sheet of Teflon, joining the two sheets at one edge. As the sound waves vibrate the two sheets in different ways, it causes the two sheets to come in and out of contact generating electricity.  The experiment is pretty similar to charge developed when a person rubs a balloon with hair.

The charge can also be converted into a range of sound frequencies, allowing the initial sounds to be amplified.

Importantly the researchers have stated that the paper thin microphone is scalable for commercialization and future use in devices like smartphones.  “It can be made into any size you like,” said Zhong Wang of the Georgia Institute of Technology. However, Wang said a stamp-sized microphone fitted to the phone would only provide a small amount of power rather than fully charging the phone.

The research team says that their concept can be adopted in variety of applications to harvest sound energy. For example the technique can be used in wearable gadgets, military equipments, in jet engines to reduce noise and even a budget-friendly human ear implant.

Resource : ACS Nano