The device is called “liquid-solid interface triboelectric nanogenerator”. The generated electricity can be stored in batteries for further use, the institute claimed.

“The device has a very simple structure consisting of specially designed nanocomposite polymers and contact electrodes and can generate a few milliwatts (mW) of power, which is sufficient to power small electronic devices like watches, digital thermometers, radio frequency transmitters, healthcare sensors, pedometers. When compared to conventional methods, such as the use of the piezoelectric effect, the present device can generate significantly more electricity,” said IIT-Delhi in a statement.

Neeraj Khare, a professor of physics, and his group at the Nanoscale Research Facility (NRF) at IIT-Delhi have been working on harvesting electrical energy from mechanical vibrations using the triboelectric effect. The group has filed an Indian patent on the various aspects of the use of ferroelectric polymer for harvesting mechanical energy including the present device.

“Triboelectric effect has been a known phenomenon for a long time, and in this effect, charges are generated when two surfaces are in friction. The best example we see are sparkling lights when we move the blankets/jackets. It is only lately that it has been extensively investigated as a practical alternative for energy harvesting,” said Khare.

In a recently published work, Khare and Huidrom Hemojit Singh note: “(I)t is demonstrated that water drop rolling over the surface of the device generates electricity.”