Seoul National University College of Engineering has announced that a research team led by Prof. Jeonghun Kwak of the Department of Electrical and Computer Engineering, with co-first authors Dr. Juhyung Park and Dr. Sun Hong Kim, has developed a flexible and thin “pseudo-transverse thermoelectric generator” capable of producing electricity from body heat. The research findings appear in Science Advances.

Thermoelectric generators, which convert temperature differences into electricity, are attracting attention as a next-generation energy technology for wearable electronics because they can supply power without batteries. In particular, thin-film thermoelectric generators are lightweight and flexible, allowing them to be comfortably attached to skin or clothing.

However, this thin structure also presents a limitation. Thermoelectric generators require a temperature difference between hot and cold sides to generate electricity. When such a device is attached flat to the skin, body heat passes directly through the thin film and dissipates into the surrounding air—similar to heat passing through a sheet of paper. As a result, little to no temperature difference is formed across the device, making electricity generation difficult.