Leaves based triboelectric nanogenerator (TENG) and TENG tree for wind energy harvesting

Triboelectric nanogenerators based on biodegradable plant leaf and leaf powder is fabricated through a simple and cost effective method. The short-circuit current (I_sc) and output voltage (V_o) of fresh leaf can reach 15 μA and 430 V. Dry leaf is grinded into powder to make solve problem of frangibility when contact and make full use of the leaf. Poly-L-Lysine is used to modify leaf powder and enhance the output performance of leaf powder based TENG. After surface modification, the I_sc and V_o can reach high as 60 μA and 1000 V, respectively, which can easily power a commercial electric watch and 868 LEDs. To extend the drive mode, wind driven TENG (WTENG) based on PLL modified leaf powder is designed for harvesting wind energy and the maximum I_sc can reach 150 μA under 7 m/s wind speed. The WTENG is designed to power an “EXIT” LED light for exit passageway in windy weather. Furthermore, TENG tree is designed basing on the live leaves and artificial leaves, which have promising potential use in the remote regions, such as in the mountains or islands, for early warning and indicator light.