Enhanced dielectric properties of freestanding, flexible, hydrophobic cellulose/poly(vinylidene fluoride) composite films

Freestanding, composite films of poly(vinylidene fluoride) (PVDF) and cellulose were synthesized and characterized for morphological, microstructural, vibrational and dielectric properties. The thickness of the freestanding films was found to be similar to 38 mu m. Contact angle measurements showed the hydrophobic nature of the composite films. Fourier transformed infrared (FTIR) spectroscopy confirmed the reduction in the alpha phase content of the PVDF films with the addition of fillers. The measured dielectric constant of the composite films was found to be more than two times than that of the pristine films An increase in the dielectric constant of the composite films was attributed to the Maxwell-Wagner-Sillars (MWS) polarization. A triboelectric nanogenerator (TENG) operating in a vertical contact-separation configuration was fabricated using these composite films. A maximum output power density of similar to 6 mu W/cm(2) was achieved from the TENG fabricated using the composite films.

Automated summary

Freestanding composite films of PVDF and cellulose were synthesized and characterized. The films exhibited hydrophobicity and increased dielectric constant compared to pristine films. A triboelectric nanogenerator fabricated using these films demonstrated a high output power density.