Energy harvesting with thermoplastic polyurethane nanofiber mat integrated with functionalized multiwalled carbon nanotubes

Triboelectric nanogenerators (TENGs) have received considerable attention as flexible and stretchable systems capable of harvesting energy and converting mechanical into electrical energy. This paper reports on Forcespinning-synthesized poly(vinylidene fluoride) (PVDF) and thermoplastic polyurethane (TPU) nanofiber (NF) membranes based TENG. To improve the TENG, the TPU NFs were decorated with multi-walled carbon nanotubes (MWCNT) functionalized with fluoride, amide, and carboxylic groups. The NF demonstrated a stronger interaction with the carboxylic-functionalized MWCNT (c-MWCNT). Furthermore, the c-MWCNT functionalized TPU/PVDF TENGs were evaluated by applying compressive force (30 psi) utilizing a pneumatic cylinder. The maximum alternating voltage, and current outputs were 158 V and 170 µA respectively. The TENG charging capacity for the samples dipped for 12 h in the c-MWCNT showed an ability to charge a 1 µF capacitor up to 3.03 V in 25 s of hand tapping, suggesting that the fabricated TENG has the capability to function as a self-charging flexible energy harvester.