Ultra-sensitive electronic skin modeled after the human brain

Pressure sensors are devices that detect a slight change or force and convert it into signals. They are used in smartphones and healthcare devices to detect touch, heart rate, and muscle movements. Similar to the human skin, the pressure sensor−based electronic skin detects slight pressure, so it is used across many different applications, including wearable devices, medical monitoring devices, and sensory systems for robots. To employ electronic skin for more practical purposes, it is indispensable to go beyond simply detecting pressure and achieve greater sensitivity, transparency, and flexibility. In this context, many studies are being conducted to improve performance.

The research team led by Professor Lee developed a pressure sensor that emulates the way the human brain transmits signals. The brain transmits signals in a complex and quick way as neurons and glial cells work together. Professor Lee's team created a network of nanoparticles modeled after this structure and designed a pressure sensor sensitive to slight pressure.

The pressure sensor developed in this study is not only highly sensitive but also highly transparent and flexible. It can detect slight changes, such as in the heart rate and finger movements, as well as the pressure of water droplets. Furthermore, it works stably even after 10,000 repeated uses, and its performance does not decline even in hot or humid environments.

Professor Lee at the Department of Energy Science and Engineering, DGIST, said, "Based on this study, we successfully developed a tactile sensor applicable to the next-generation electronic skin with transparency and flexibility. Hopefully, research on the basic mechanism of how the sensor works will continue, leading to the development of artificial tactile sensors that simulate the human skin and the technological development of transparent displays for commercialization."

This study was conducted jointly by Jiwoo Koo, a PhD program student at the Department of Materials Science and Engineering, Seoul National University; Dr. Jongyoon Kim at the Department of Energy Science and Engineering, DGIST; Dr. Myungseok Ko, Jeonbuk National University; Professor Youngu Lee, DGIST; and Professor Jaehyuk Lim, Jeonbuk National University. In addition, the study was funded by the National Research Foundation of Korea's Mid-Career Research Project and the Sustainable Solar Energy Use Engineering Research Center Project, and its results were published in the October 2024 issue of the Chemical Engineering Journal, an international journal in the field of chemical engineering.