The researchers shared their findings in a paper titled “High-output, transparent, stretchable triboelectric nanogenerator based on carbon nanotube thin film toward wearable energy harvesters” published in the Nano Energy journal. The paper reports several proof-of-concept stretchable TENGs, including a 12x12cm unit, 92% transparent and able to power 30 blue LEDs connected in series for each gentle tap from a hand. The authors also attached a 500μm thin TENG to the palm of a nitride glove, connecting it to a string of 16 blue LEDs on the back of the glove. Gentle claps were enough to instantly power the LEDs, with a current density as high as 48mA/m2.
Unlike previously reported stretchable TENGs whose output power remains usually insufficient for practical use, here the authors report an output power up to 8W/m2 for devices only requiring a simple fabrication process such as spray coating, which could easily be scaled up to large areas.
Key to the high TENG efficiency and durability, even under strain, is the use of a carbon nanotube (CNT) thin film, made of a randomly oriented single-walled CNT network. The CNTs form an excellent stretchable conductor with high electrical conductivity, optical transparency, mechanical durability, and chemical stability. The stretchable TENG’s output power was also optimized by modifying the transparent elastomer (PDMS) surface with a fluorinated plasma.
Nagoya University – en.nagoya-u.ac.jp