Effect of reduced graphene oxide on the energy harvesting performance of P(VDF-TrFE)-BaTiO₃ nanocomposite devices

Abstract

This study investigates the effect of reduced graphene oxide (rGO) on the energy harvesting performance of poly(vinylidenefluoride-trifluoroethylene)-barium titanate (P(VDF-TrFE)-BTO) nanocomposite devices. Several piezoelectric nanogenerators with different rGO contents were prepared, among them PBR5-NG (rGO = 0.5%) exhibited maximum output performance. PBR5-NG showed a maximum open circuit voltage of 8.5 Vpk–pk and short circuit current of 2 μApk–pk at an applied force of 2 N. Moreover, PBR5-NG displayed an output power of 4.5 μW at 2 MΩ load resistance. To confirm device stability, the fabricated device was subjected to several pressing-releasing cycles. The device had excellent stability, even after 1000 pressing-releasing cycles. Together, our results indicate that our fabricated PBR5-NG is a promising energy source for future flexible electronics.

Hybrid lead-free polymer-based nanocomposites with improved piezoelectric response for biomedical energy-harvesting applications: A review

“…The addition of MgO into the polymer matrix reportedly induced an improvement in the crystallinity of the latter, which was attributed to the formation of hydrogen bonds between the inherently present −OH groups on the MgO surface and the F atoms of PVDF-TrFE [58]. The values of the piezoelectric coefficient d 33 Owing to its exceptional mechanical and thermal stability, TiO 2 is another semiconductor that can be used to develop high-performance PVDF-based NGs for energy harvesting and storage applications [91]. Alam et al prepared a flexible and wearable NG for harvesting mechanical energy from normal human activities and acoustic vibrations from an electrospun PVDF/TiO 2 fibre mat from an electrospun PVDF/TiO 2 fibre mat.…”

“…It is well documented that adding conductive fillers to composite materials can not only further increase their dielectric constant and piezoelectric charge constant values due to the formation of micro-capacitors inside the composite, but also contributes to the stabilization the polar β-phase of the polymer matrix [33]. Uniform dispersion of the piezoelectric particles in composite films is essential for the fabrication of composite-based PENGs with a high output, as it ensures a well-distributed piezopotential within the active energy-harvesting composite layer [129].…”

“…PZT materials have been broadly commercialised; for example, a flexible multi-layered composite for low frequency energy harvesting applications was prepared based on PET/Al/PZT/Al/PET [5]. Well-aligned PZT NRs prepared via hydrothermal treatment with (001)-orientated tetragonal single crystalline structures exhibited a high piezoelectric response with a d 33 value of up to 1600 pm·V -1 . A piezoelectric energy harvester was fabricated based on the PZT NR arrays and exhibited an outstanding energy harvesting performance with opencircuit output voltages of 3.3 V and 8 V when subjected to a compressive 10 N force and a finger tapping motion, respectively.…”

“…The application of high voltages during the electrospinning process essentially leads to the alignment of the electric dipoles present in the PVDF solution, with the degree of alignment being proportional to the magnitude of the applied electric field [26]. Various electrospun hybrid composites for energy-harvesting applications based on PVDF or PVDF-TrFE nanofibre mats, including graphene nanosheets and BT NPs [27], (Na0.5,K0.5)NbO 3 (NKN) NPs embedded in PVDF-TrFE [12], BT NPs embedded in PVDF-TrFE [28,29], PVDF-ZnO nanofibre mats [26], PVDF/KNN NRs [30], K0.5Na0.5NbO 3 -BT/PVDF [31], Ag/PVDF-TrFE [32], and PVDF-TrFE-BT with rGO contents of 0.1%, 0.3%, 0.5%, and 0.7% [33] have been reported. Structurally robust, reproducibly scalable, substrate-independent, and large-area NGs have been successfully fabricated utilizing the near-field electrospinning direct-write technique to massively align the piezoelectric PVDF nanofibres (NFs) on flexible substrates [34].…”

“…The degree of crystallinity plays an important role in the d 33 piezoelectric response, which increases with the degree of crystallinity for a piezoelectric polymer [42], allowing greater piezoelectric potential values to be obtained. For example, a PVDF harvester provided an average output power of 1 mW during a walk at a frequency of roughly 1 Hz [43].…”