An ink ‘writes’ tiny generators that are powered by heat

Energy

11 August 2021

Printing technique could help to produce minute power sources for use in lightweight sensors and wearable devices.

With the help of a new 3D-printing ink, scientists have crafted a miniature generator that efficiently transforms the flow of heat into an electric current.

Thermoelectric materials generate electricity from the movement of a modest amount of heat from a warmer place to a cooler one. But scientists have struggled to make thermoelectric components small enough to be useful in items such as wireless sensors.

Han Gi Chae and Jae Sung Son at the Ulsan National Institute of Science and Technology in South Korea and their colleagues sought to make small, 3D-printed components by tinkering with the ink recipe. By optimizing the ink formula for microscale fabrication, the researchers were able to print slender, sturdy columns 1.4 millimetres tall and less than 0.5 millimetres in diameter onto a silicon chip. When the team heated one side of these columns while cooling the other, the micro-generator produced enough electricity to run a wireless sensor network.

The authors hope that this technique will make it easier to incorporate thermoelectric generators into wearable electronics, perhaps allowing the generators to replace conventional batteries.