GnPs/PVDF decorated thermoplastic veils to boost the triboelectric nanogenerator output performance toward highly efficient energy harvesting

Abstract

Triboelectric nanogenerators (TENGs) are state-of-the-art devices that generate electricity through the coupling effect of triboelectrification and electrostatic induction by harvesting mechanical energy. This study aims to boost the electrical performance of a TENG that harvests biomechanical energy to power wearable and portable electronic devices by employing a simple and inexpensive method based on GnPs. For this purpose, I have designed and produced a vertical-contact-separation mode TENG suitable for biomechanical energy harvesting using tribonegative materials Polyvinylidene difluoride (PVDF)/ Polyetheretherketone (PEEK) veil and tribopositive materials Polyethylene oxide (PEO)/ Glass and Nylon 6.6 nanofibers. The surface of the PEEK veil is coated with a PVDF solution with excellent tribonegativity and ferroelectric polarization properties using the doctor blade technique. The electrical performance of the TENG is assessed by connecting a capacitor or various load resistors to the circuit. 3 wt% GnPs@PVDF/PEEK & Nylon 6.6 nanofibers and 3 wt% GnPs@PVDF/PEEK & PEO/Glass veil TENGs deliver output voltages of 470 V and 303 V, respectively at 75.8 MΩ load resistance. The power densities of 3 wt% GnPs@PVDF/PEEK & Nylon 6.6 nanofibers and 3 wt% GnPs@PVDF/PEEK & PEO/Glass veil TENGs at 1.1 MΩ are 7.36 W/m2 and 4.04 W/m2, respectively. Root mean square (RRMS), peak to peak height (Rpp), and arithmetic mean height (Ra) of the surface roughness of 3 wt% GnPs@PVDF/PEEK are measured to be 17.59 µm, 151.08 µm, and 13.16 µm, respectively. Parallel to increased surface roughness, the output power, and output voltage of 3 wt% GnPs@PVDF/PEEK & PEO/Glass veil TENG increase by 4 and 2.23-fold, respectively. Further GnPs embedding reduces both surface roughness and electrical performance of the TENG. I believe that GnPs@PVDF/PEEK veil material has the potential to be used to make high-performance TENGs that can power portable, wearable, and self-powered electronics.