PVDF has special piezo/pyro/ferroelectric, flexibility, low weight, biocompatibility, economical, good chemical/thermal, and high mechanical properties such as excellent nontoxic fiber/film formation. It has polar and nonpolar phases of α, β, γ, ε, and δ that the nonpolar α phase is the most stable one, but the β phase is the best of all because it has good piezo/pyro/ferroelectric properties. Copolymers are attractive because of their low weight, nontoxic, chemical acid resistance, flexibility, and ease of processing. These aspects result in their applications in many fields. They are used for piezoelectric nanogenerators, cooling/heating sensors, electronic devices (fuel cells, lithium-ion batteries (as separators), dye sensitive solar cells), filtration, oil/water separation, and photoelectric nanodevices. This review highlights the main aspects of the last decade’s articles, and the focus is on the synthesis methods of PVDF nanofibers and their properties which results in their application in different fields of industry and especially focuses on finding ways to increase the output of PVDF nanofibers nanogenerators (weight/acoustic pressure nanogenerators).

Here away used to reduce the porosity of the nanofibers, which is removing polyvinyl alcohol (PVA) nanofibers from PVA/poly amide 6 (PA6) nanofibers by water treatment. Measuring the porosity of the electrospun web before and after treatment by the Brunauer, Emmett and Teller (BET) method proved this. The specific surface area of the web was 60 % reduced after water treatment. Surface roughness and pore volume have reduced after water treatment. Also, I introduced BET as the method for measuring the diameters of mesopores (or lower than 100nm). I used BET to prove that the cracks can make mesopores on the nanofibers.

Here away used to reduce the porosity of the nanofibers, which is removing polyvinyl alcohol (PVA) nanofibers from PVA/poly amide 6 (PA6) nanofibers by water treatment. Measuring the porosity of the electrospun web before and after treatment by the Brunauer, Emmett and Teller (BET) method proved this. The specific surface area of the web was 60 % reduced after water treatment. Surface roughness and pore volume have reduced after water treatment. Also, I introduced BET as the method for measuring the diameters of mesopores (or lower than 100nm). I used BET to prove that the cracks can make mesopores on the nanofibers.

In recent years, piezoelectric nanogenerators, due to their greater durability in high dust or humidity, have become more attractive than triboelectric nanogenerators. Therefore, increasing their outputs is the subject of many studies. I focused on electrodes of acoustic nanofiber nanogenerators for the first time. Compared to other works here, I want to introduce a new electrode that is cheaper and does not result in lower outputs. Here, for the first time, graphene spincoated ink was used for a polyacrylonitrile-based acoustic nanogenerator. The results of the acoustic tests were compared with the in- situ synthesis of nickel nanoparticles on the layer using graphene spin-coated screen ink and conductive tape.

In the recent years piezoelectric nanogenerators due to their more durability in high dust or humidity are mor attractive than triboelectric ones. So, increasing the outputs of them is the subject of many researches. I focused on electrodes of the acoustic nanofibers nanogenerators for the first time. Compare to other works here I want to introduce a new electrode which is cheaper and do not result in lower outputs. Here for the first time, graphene spin coated ink used for polyacrylonitrile based acoustic nanogenerator. The results of the acoustic tests compared with in-situ synthesis of nickel nanoparticles on the layer and using graphene spin coated screen ink and using conductive tapes. Finally, producing sound by this graphene ink was done too.