The College of Nano Science and Technology of China's Soochow University has developed a combo solar panel/triboelectric nanogenerator (TENG), capable of power generation during rainy days.
TENG is based on contact electrification on which certain materials become electrically charged after they come into frictional contact with a different material. The Soochow U. team designed an energy collection system taking advantage of the power generated by friction between raindrops and solar energy. Its researchers place two transparent layers of polymer on solar panel, polydimethylsiloxane on top of PEDOT:PSS,. with former being a frictional material and the latter the common electrode for solar panel and TENG.
During rainy days, TENG will function, transmitting power to solar panel via PEDOT:PSS, substituting for solar panel which collect energy from sunshine during sunny days, as the two transparent polymer layers wouldn't block sunlight.
The device is still an experimental one, with short-circuit current at 33nA and open-circuit voltage at 2.14 V. The team has developed a new version featuring simpler design and smaller size, easier for manufacturing. The research result has been published in "ACS Nano" journal.
(Article by Daisy Chuang; photo courtesy of ACS Nano)