Development of large-scale electret fabrication system for triboelectric nanogenerator electrical output amplification

Abstract

The triboelectric nanogenerator (TENG), which converts mechanical energy to electrical output, is garnering attention owing to their application in low-energy electronic devices as a power source. To utilize the TENG as a power source, amplifying the electrical output and enhancing energy conversion efficiency are necessary. As the TENG generates electrical output through contact electrification and electrostatic charge induction, the electrical output can be amplified by enhancing the two mechanisms through the enlargement of the TENG area and the adoption of the pre-charge injected film (electret). In this regard, the fabrication of the large-scale electret is significant for amplifying the electrical output of the TENG. In this study, a corona charging system is proposed for the fabrication of the large-scale electret with a uniform charge-distributed area. Corona charging injects O2 ions into a dielectric film with an electric field generated between the pin electrode (PE) and ground electrode (GE). Through the utilization of a multi-PE (MPE) and conveyor belt-shaped GE (CBsGE) in the corona charging system, the O2 molecules near the pins can be ionized simultaneously while the CBsGE is rotating. Thus, the O2 ions can be injected uniformly into a wide area. About a voltage of 400 V and current of 45 μA can be generated by applying the fabricated electret to the TENG. As several electrets with various sizes can be fabricated simultaneously, the TENG with high electrical output can be batch fabricated to enhance its practicality significantly.

Recent Advances in Triboelectric Nanogenerators: From Technological Progress to Commercial Applications

“…In principle, triboelectric nanogenerators (TENGs) generate an electrical energy from surrounding mechanical energy due to the coupling effect of contact electrification and electrostatic induction . The contact electrification is physically the result of charge transfer when two different materials are charged after contact and separation . This can occur between two pieces of the chemically same material because the surfaces are not commonly uniform.…”

“… 71 The contact electrification is physically the result of charge transfer when two different materials are charged after contact and separation. 72 This can occur between two pieces of the chemically same material because the surfaces are not commonly uniform. Such a situation is common in nature and human life and is also responsible for lightning in thunderstorms.…”

Inhibiting scar formation via wearable multilayer stacked electret patch: Self‐creation of persistent and customizable DC electric field for fibrogenic activity restriction

“…An electret is a dielectric material that exhibits a quasipermanent electric charge or dipole polarization and provides stable EF as one of the electrical stimulations. 40,48,49 Here, a fluorinated ethylene propylene (FEP) film, which is well known as a commercial material for electrets owing to its outstanding charge trapping properties, was adopted as a candidate for corona charging. 46,48,50 For the fabrication of a uniformly charged electret over the area, the corona charging system was set up with the needlegrid electrode (Figure 2A).…”

“…40,48,49 Here, a fluorinated ethylene propylene (FEP) film, which is well known as a commercial material for electrets owing to its outstanding charge trapping properties, was adopted as a candidate for corona charging. 46,48,50 For the fabrication of a uniformly charged electret over the area, the corona charging system was set up with the needlegrid electrode (Figure 2A). Thus, neutral air close to the needle electrode can be ionized when a high voltage is applied to the sharp-shaped needle electrode, which can generate a substantially high EF strength at a relatively low voltage input.…”