Triboelectric generators (TEG) or triboelectric nanogenerators (TENG) are the emerging effective wasted mechanical-electrical energy conversion devices. This energy source can be used powerfully in light emission and energy storage for various electronic applications.

The principle is based on triboelectric effect and electrostatic induction between two triboelectric surfaces. It is generally constructed following the cycling contact-separation mode of two triboelectric materials. The triboelectric material can be a metal, non-metal, or compound materials, which can electrically charge by the contact and friction with other triboelectric materials. The output performance of the TEG/TENG strongly depends on the contact area and friction between the two tribo-electric materials. On ther other hand, in limited area of two triboelectric surfaces, the contact area and friction is strongly related to the morphology.

In this work, a facile method and novel mechanism using microneedle (MN) structured polydimethysiloxane (PDMS) are applied for TEG/TENG applications. The MN-TEG is the TEG device consisting of an aluminum foil and a microneedle-structured polydimethylsiloxane (MN-PDMS) film. The MN-PDMS was fabricated by a simple, low-cost, rapid-fabrication method using CO2 laser ablation on a polymethyl methacrylate master mold and molding process. The MN-TEG can convert wasted mechanical energy into electricity. The special characteristic of MN-PDMS is great increase of randomly closed bending-friction-deformation behavior of MNs that highly enhances triboelectric performance of the MN-TEG. By hand tapping, the new high-aspect-ratio MN-TEG can generate high output performance with the open-circuit voltage up to 102.8 V and the short-circuit current of 43.1 A, corresponding to the current density of 1.5 A cm-2. The MN-TEG’s durable mechanical working was confirmed over 500 min, that is, more than twenty-time tapping of 1500 sec stable electric power generation. The output energy of the MN-TEG can be stored in capacitors with fast charging and high charging voltage, for example, on a 0.1 F capacitor up to 2.1 V in about 0.56 sec simply by hand tapping. The MN-TEG source under tapping can directly light up 53 LEDs with different colors connected in series.

Please refer the details to http://dx.doi.org/10.1002/smll.201700373 for “How the entry works, what makes it novel, how it would be produced, and where it would be applied”.