A revolutionary thermoelectric material and generator has been developed by a team of researchers in Korea, utilizing sponge-like carbon nanotube (CNT) structures to overcome the limitations of traditional organic thermoelectric materials while retaining flexibility. This innovative device is poised to power small wearable sensors through thermal energy harvesting.
Published in the journal Carbon Energy, the research led by Drs. Mijeong Han and Young Hun Kang at the Korea Research Institute of Chemical Technology (KRICT) combines carbon nanotubes with Bi0.45Sb1.55Te3 (BST) in a porous foam structure to maximize thermoelectric performance.
Unlike conventional metal-based and rigid thermoelectric materials, the use of CNTs allows for lightweight and mechanical flexibility. Previous attempts using CNTs have faced challenges such as low thermoelectric performance and poor durability. To address these issues, the research team developed a unique fabrication technique that transforms CNTs into bulk foams rather than thin films. This was achieved by heating and solidifying a powder-filled mold to create a sponge-like structure.
Furthermore, a method was devised to evenly distribute the thermoelectric BST particles within the foam’s pores, enhancing both mechanical stability and thermoelectric performance. As a result, the CNT/BST foam achieved a zT value of 7.8 Ă 10-3â5.7 times higher than pristine CNT foam. When applied to a flexible thermoelectric generator and tested on a glass tube with a temperature difference of 21.8 K, the device generated an output power of 15.7 ”Wâsufficient to operate wearable sensors.
The durability of the device was confirmed through 10,000-cycle bending tests with minimal performance loss. Moreover, the entire fabrication process takes just four hours, significantly faster than traditional CNT-based TEGs which can take over three days, showcasing the material’s scalability.
The research team aims to further enhance thermoelectric efficiency through doping strategies and targets commercialization by 2030. Future applications include integration into thermal management systems for batteries, AI data centers, as well as wearable and autonomous electronic devices. The researchers stated that the material’s moldability and durability offer new possibilities in energy harvesting and represent a significant advancement in flexible, self-powered devices.
For more information, the full study can be found in the journal Carbon Energy under the title “Highâperformance and flexible thermoelectric generator based on a robust carbon nanotube/BiSbTe foam” by Myeong Hoon Jeong et al.
This groundbreaking development in thermoelectric technology opens up new avenues for energy harvesting and promises a more sustainable future for wearable technology and electronic devices.
