Electricity Generated with a Simple Touch... UNIST Develops Adhesive Film That Creates Electrical Signals

Adhesive Film with 35 Times Stronger Adhesion and 13 Times Higher Output Developed by Jeong Hoonui's Team
Applications in Anti-Theft and Industrial Safety Technologies, Published in Advanced Functional Materials

All that is visible is a thin film. However, the moment a thief opens the door, an alarm sounds, and even before a picture frame falls, a notification is sent to a smartphone.

In factories, machines stop immediately as soon as a conveyor belt begins to run in reverse. This is made possible by an adhesive film that generates electricity simply through attaching and detaching motions.

A domestic research team has developed such an electricity-generating film.

The team led by Professor Jeong Hoonui from the Department of Mechanical Engineering at UNIST has newly developed a triboelectric generator film that can simultaneously control both adhesive strength and electrical output.

Research team (from left) Professor Jeong Hoonui, Researcher Lee Heejin, Researcher Kang Donggwan (first author), Researcher Kang Junghwa. Provided by UNIST

Triboelectric generation is based on the principle that electricity is generated when two materials come into contact and then separate, causing charges to move. The research team applied this principle to an adhesive film, enabling it to generate electrical signals through simple attaching and detaching motions without the need for an external power source.

This film features a 'ㄷ'-shaped incision pattern, which provides more than 35 times greater adhesive strength and about 13 times higher electrical output compared to conventional films. Thanks to this, even short and simple movements, such as pressing and releasing by hand or a slight drop of an object, can generate strong electrical signals from the film.

Lee Heejin, the first author and researcher, explained, "The incision pattern controls the direction in which cracks propagate and increases instantaneous adhesive strength. In particular, we utilized the phenomenon where, when a crack stops at the junction and then proceeds in the opposite direction, rapid separation occurs, resulting in a significant increase in electrical output."

Another advantage of this film is that by changing the direction and arrangement of the incision pattern, the output and adhesive strength can be designed to vary depending on the direction or location of attachment.

The research team also verified its practical applicability. By attaching the film to a door gap, they created a system where an electrical signal is generated as soon as the door opens, triggering an alarm. They also developed a system that detects the peeling motion before a picture frame attached to a wall falls and sends a warning to a smartphone.

Additionally, by attaching the film to a conveyor belt, they designed it so that an electrical signal is generated only when the belt rotates in reverse, not during normal operation, allowing machines to stop in the event of abnormal operation.

Structure of triboelectric adhesive film, magnitude of electrical signal, and adhesive strength.

Professor Jeong Hoonui stated, "This technology transforms adhesive film from a simple attachment-detachment tool into a smart sensor that generates its own electrical signals. It can perform both detection and signal generation without batteries, making it suitable for simple-structured sensing systems, and it is expected to be applicable in a wide range of fields such as wearable sensors, anti-theft devices, and industrial safety systems."

This research was published in the world-renowned journal 'Advanced Functional Materials' on June 11, 2025, and was supported by the National Research Foundation of Korea and the Ministry of Science and ICT.

This content was produced with the assistance of AI translation services.