Tailoring the Output Performance of PVDF-Based Piezo–Tribo Hybridized Nanogenerators via B, N-Codoped Reduced Graphene Oxide

Recently, piezoelectric and triboelectric nanogenerators are explored extensively for harvesting energy from mechanical vibrations via piezoelectric and triboelectric effects. The output efficiency of these nanogenerators can be improved further by combining their piezoelectric and triboelectric effects to fabricate a hybrid nanogenerator. In the present work, first, piezoelectric energy harvesters are fabricated to investigate the effects of the introduction of reduced graphene oxide (rGO), single-heteroatom (N)-doped rGO, and boron/nitrogen-codoped rGO in enhancing the piezoelectric performance of a poly(vinylidene fluoride) (PVDF)-based nanogenerator. Then, the film showing the highest piezoelectric performance (i.e., PVDF/BN-rGO) is coupled with a PDMS film to fabricate a hybrid nanogenerator. In comparison to a pristine PVDF-based nanogenerator, the PVDF/BN-rGO-based piezoelectric nanogenerator device exhibits ∼2 times enhancement in output voltage and ∼6 times enhancement in piezoelectric current, whereas the hybrid nanogenerator with the corresponding composite film shows better electrical performance, producing an output voltage and current of 57.6 V and 28.8 μA, respectively. The improved performance of the nanogenerator is ascribed to the synergistic effect of piezoelectric and triboelectric effects together with the addition of codoped rGO in the PVDF matrix, which increases the remnant polarization and dielectric property of the PVDF nanocomposite film. Finally, the output generated by the hybrid nanogenerator is used to power 15 light-emitting diodes (LEDs) and a calculator. The present work has shown the importance of rGO and its derivatives for energy harvesting applications.