Systematic investigation of the effect of SnS2 nanofiller content on the piezoelectric performance of the PVDF-TrFE-based nanogenerator

Abstract

In this work, SnS2 is used as a nanofiller material to improve the response of the polymer-based piezoelectric nanogenerator because of its better inherent piezoelectric properties in comparison to other 2D materials. For this, first, nanoflakes of tin sulfide (SnS2) were synthesized via the hydrothermal method, where the high purity of SnS2 powder is confirmed by Raman spectroscopy and X-ray diffraction studies. The obtained powder of SnS2 was then mixed with PVDF-TrFE in different weight percentages (0%, 1%, 3%, 5%, and 7%) of SnS2 to synthesize polymer composite films via drop-casting method. These films are then characterized with XRD and FTIR spectrometers which show enhancement in the electroactive beta phase of the nanocomposite films after doping of SnS2 powder, from 58.30% to 93.07%, which is in agreement with the polarization versus electric field (P-E) measurements that show increased remnant polarization after doping. These films are then used to fabricate a piezoelectric nanogenerator by adhering aluminum tape on both sides of the films. The piezoelectric nanogenerator's (PENG) output performance is analyzed by measuring the open-circuit voltage (Voc) and short-circuit (Isc) by tapping the nanogenerator with the help of a dynamic shaker, which shows that the output performance of PVDF-TrFE based PENGs gets enhanced after the introduction of SnS2 powder. The maximum output voltage of 14.4 V is obtained corresponding to the PENG with 5 wt% SnS2, which was almost 1.5 times that of the PENG made with bare PVDF-TrFE. The output piezoelectric current follows the similar trend, with the 5 wt% SnS2 PENG producing3.9μA of current, which was roughly 1.62 times more than the output of the bare PVDF-TrFE thin film. As a result, the present study demonstrates that adding SnS2 to the PVDF matrix can significantly improve energy harvesting technologies based on PVDF's piezoelectric properties.