Fully biodegradable triboelectric nanogenerators based on electrospun polylactic acid and nanostructured gelatin films

Here, we present a fully biodegradable triboelectric nanogenerator (BD-TENG) based on gelatin film and electrospun polylactic acid nanofiber membrane. By optimizing the material properties of the gelatin and PLA polymer films, an output voltage up to 500 V, a short circuit current density of 10.6 mA/m(2) and a maximum power density over 5 W/m(2) are achieved with a device dimension of 4 x 4 cm(2). Performance of the BD-TENGs using different material combinations under various test conditions are investigated and analyzed. The BD-TENGs show excellent mechanical stability and reliability upon cyclical contact for up to 15,000 times. Biodegradation experiments show that all the materials of the TENG could be degraded completely into water in about 40 days. The BD-TENGs provide a promising green micro-power source for environment monitoring, biomedical implants through harvesting energy from wind, heart motion et al., yet they can dissolve with no adverse effect to environment or human body.