Scientists from Clemson University, U.S. have developed a new tribolelectric nanogenerator that can generate over 2,000 volts just by tapping on it and also wirelessly transfer the energy produced to a nearby battery. The scientists say that this is the first time wireless transmission of electrical energy has been achieved. It is also the first time a triboelectric nanogenrator has been directly 3D printed from biodegradable materials.
The nanogenerator harvests mechanical energy and converts into electrical energy and transferred wirelessly over a distance of three metres to a storage device like capacitor or battery.
“We can install the nanogenerator at airports, sidewalks and place the battery on the nearby walls to store the energy. Because there are no wires involved, there is no need of power outlets and can be installed easily,” says Prof. Ramakrishna Podilla at the Laboratory of Nano-Biophysics and Clemson Nanomaterials Institute, Clemson University, Clemson, South Carolina, U.S.
These generators have a wide range of applications. They can be used to light up our homes, control doors and even set burglar alarms. The scientists are now working on developing fingerprint sensitive generators for home-security applications.
Generator set-up
The main component of the generator is polylactic acid, a plant derived polymer. Since polylactic acid has a high electrical resistance, the scientists incorporated graphene to improve the conductivity while retaining the polymers ability to be polarized.
“The generator is made of graphene-polylactic acid layer on the bottom and a Teflon layer on top. When these twomaterials with very different electro negativity come into contact, they produce large voltages. Just one hand tap is enough to produce current of 2000 volts,” explains Prof. Podilla who is corresponding author of the paper published in Advanced Energy Materials . The nanogenerator was capable of producing an instant peak power up to 70 milliWatts.
“The device produces electric fields at two unique frequencies. Using these frequencies, we custom built an inexpensive wireless signal processing circuit with an inbuilt filter. This will help avoid interference from the environment including WiFi routers, mobile phones, and AC power outlets,” Sai Sunil Kumar Mallineni, a graduate student at Clemson Nanomaterials Institute and first author of the paper published in Advanced Energy Materials says in an e-mail to The Hindu .
