A Triboelectric Generator Based on Checker‐Like Interdigital Electrodes with a Sandwiched PET Thin Film for Harvesting Sliding Energy in All Directions

Abstract

external action, two triboelectric layers with opposite triboelectric charges periodically contact and separate from each other, which changes the induced potential difference between the two electrodes to drive an alternating current fl owing between the electrodes. For the previous TENGs, the two triboelectric layers are bonded to different objects, one of which needs to move working as the mechanical energy source. On the surface of the two triboelectric layers each is attached to a metal electrode and a conducting wire. Due to intertwinement of the wires in the moving process, such a device confi guration largely limits the multifunctionality and applicability of TENGs for harvesting energy. In addition, the interface between the metal electrodes and moving polymers are usually rough to increase friction charge density, which limits the operating life of the generators. Very recently, the freestanding-triboelectric-layer based nanogenerator without an attached electrode has been developed to solve these problems. [ 25,26 ] In reference to the planar TENGs, the previous devices could only harvest the kinetic energy along one direction, horizontally or vertically [ 23,27 ] or rotarily. [ 28,29 ] It is necessary that the structure of the TENGs' electrodes be improved so that they can harvest energy from all directions with advantages of being fl exible, light weight, durable, cost effective, and portable.Here, we develop a triboelectric generator based on a novel checker-like interdigital electrodes (TEGC) with a sandwiched polyethylene terephthalate (PET) thin fi lm between the sliding panel and electrodes that can harvest translational motion energy in all directions. Because the interdigital electrodes are divided into many regularly aligned pieces on each branch, a casual motion of the polytetrafl uoroethylene (PTFE) squares on the sliding panel in some direction can lead to a separation and contact of charges and thereby generate electricity. As the electrodes for charge transfer are in the same plane, the output electricity from the immovable electrodes is not affected by movement of the sliding panel. Electret PTFE fi lm is used for its high ability of holding charges (charge densities up to 5 × 10 −4 C m −2 with a theoretical lifetime of hundreds of years) and relatively high mechanical behavior. [ 8 ] The working current generating mechanism and performance in different A triboelectric generator based on checker-like interdigital electrodes (TEGC) with a sandwiched polyethylene terephthalate (PET) thin fi lm that can convert translation kinetic energy in all directions to electricity is reported. The design of the sandwiched PET thin fi lm can effectively avoid direct wear between metal electrodes and sliding panel. The mechanism of the TEGC is described in detail. The performance of the TEGC in different sliding directions is studied, indicating a maximum output power density of 1.9 W m −2 and open-circuit voltage of 210 V achieved in the X or Y sliding direction. The TEGC is used to charge a 110 µF co...

Honeycomb-like three electrodes based triboelectric generator for harvesting energy in full space and as a self-powered vibration alertor

“…The maximum output current density, voltage and power density can reach 16.4 mA/m 2 , 413 V, and 2.1 W/m 2 ,respectively, by working in plane sliding mode, which is a little higher than that of the checker-like interdigital electrodes [25] and in the same level with other papers reported [26,27]. Meanwhile, the three-electrode structure can be installed in an inner surface of a spherical shell and work as an independent generator harvesting vibration energy in full space or as a vibration alertor to sense all direction vibration with high sensitivity.…”

“…However, in previous reports, most of TENGs can only harvest energy in one direction due to their simple electrode structures. Very recently, Guo et al reported the TENG based on checkerlike interdigital electrodes for harvesting sliding energy in all direction [25]. As they pointed out, the generator has two off states.…”

Recent progress on flexible nanogenerators toward self‐powered systems

“…TENGs with SFT structure can harvest energy from moving objects while the system can still mobile without grounding wires, which is suitable for harvesting rotating motion energy, human walking, and air flow, etc. Guo et al reported a TENG consisting of checker‐like interdigital metal electrodes (aluminum [Al]) and a sandwiched PET film, which can convert translational kinetic energy in all directions as shown in Figure C. When the PTFE squares and acrylic of the sliding pane move in certain direction, electricity is generated upon the separation and contact.…”

A super-flexible and lightweight membrane for energy harvesting

“…The bottom electrode has the same configuration but with a 0.8 mm offset along X-axis. Since each square has an overlapped area with the adjacent squares, the breakage or linkage of any square will not affect the performance of the arrayed device, thus improving the robustness compared with previous checker-like electrode structure [17]. To facilitate the analysis of the working principle, enlarged structure of each single unit is shown in Fig.…”