QUT researchers have overcome a challenge that has limited next-generation energy-harvesting materials for more than two decades, opening the door to more powerful wearable electronics and new ways of turning wasted heat into electricity.
The breakthrough centres on carbon nanotubes, which are flexible and conductive microscopic rods that have long shown promise for wearable technologies but have been difficult to control.
QUT researchers have now developed a new molecular strategy that prevents the nanotubes from clumping together and losing performance, enabling a new benchmark for materials that convert heat directly into electricity.
Lead author and QUT PhD researcher Mrs Shanshan Zhou said the work established a new way of tackling one of the biggest challenges facing carbon nanotubes.
“Instead of trying to improve existing approaches, we came up with a completely new way to stop carbon nanotubes sticking together, which has been a major challenge for researchers for years,” Mrs Zhou said.
“Because the approach is so flexible, it could be used to create a new generation of higher-performing materials for harvesting energy from heat.”
Published in Angewandte Chemie International Edition, the research delivered a record thermoelectric performance, surpassing benchmark researchers in the field have been striving to reach for years.
Professor Zhi-Gang Chen, Director of the ARC Research Hub in Zero-Emission Power Generation for Carbon Neutrality, said carbon nanotubes had enormous potential, but one persistent problem had stood in the way.
“For many years, researchers have recognised that carbon nanotubes are excellent candidates for wearable thermoelectric devices because they are lightweight, flexible and electrically conductive. However, their tendency to aggregate has severely limited their performance.”
“Our new molecular design fundamentally changes how carbon nanotubes interact with each other.
“Instead of allowing them to clump together, we use specially designed molecules to keep the nanotubes apart without affecting their ability to carry electricity.”
The researchers demonstrated the material’s real-world promise in a flexible device that generated electricity from body heat and remained durable after extensive bending and folding tests.
Professor Chen said the technology could eventually enable battery-free wearable devices.
“Imagine health monitoring sensors, smart textiles or wearable electronics that continuously harvest energy from your own body heat instead of relying on conventional batteries,” he said.
Beyond wearable electronics, the researchers believe the technology could be applied to waste heat recovery, flexible sensors, the Internet of Things and next-generation sustainable electronics.
Professor Chen said the discovery complements QUT’s broader research on zero-emission energy technologies.
“At QUT, we are developing technologies that convert otherwise wasted heat into useful electricity. This work represents another important step towards sustainable, flexible energy systems that can power future wearable and portable electronics,” Professor Chen said.
The research team included Shanshan Zhou, Dr Xiao-Lei Shi, Dr Meng Li, Dr Wenyi Chen, Dr Tianyi Cao, Nan-Hai Li, Dr Min Zhang, Professor Prashant Sonar, Dr Qian Liu, and Professor Zhi-Gang Chen, from the ARC Research Hub in Zero-Emission Power Generation for Carbon Neutrality, the QUT School of Chemistry and Physics, and Centre for Materials Science.
The research was supported by the Australian Research Council and QUT’s Capacity Building Professor Program.
Read the full study, Radical-Mediated Dispersion Breaks Aggregation Limits in Carbon Thermoelectrics in the journal Angewandte Chemie International Edition, online.
Top photo: Nanhai Li, Professor Zhi-Gang Chen, Dr Xiao-Lei Shi, Mrs Shanshan Zhou, Dr Meng Li, Professor Prashant Sonar, Dr Wenyi Chen.
