A team of researchers from the Research Institute for Electronic Science at Hokkaido University has made a major leap forward in heat management thanks to new cerium oxide-based thermal switches. These innovative devices offer a highly efficient, sustainable solution to controlling heat flow, opening doors for a range of exciting applications.
An artistic representation of a thermal switch. Image Credit: Hiromichi Ohta
Thermal switches, which regulate heat transfer through electrical signals, are critical for advanced cooling systems. Until now, their widespread use has been limited by less-than-ideal performance. This has been a hurdle for industries like electronics, energy systems, and waste heat recovery.
Professor Hiromichi Ohta and his team at Hokkaido University’s Research Institute for Electronic Science have tackled this challenge by using thin films of cerium oxide (CeO2) as the active material in thermal switches. Their breakthrough research, recently published in Science Advances, highlights a solution that’s both highly effective and environmentally friendly.
The novel device features an on/off thermal conductivity ratio of 5.8 and a thermal conductivity (κ)-switching width of 10.3 W/m·K, establishing a new benchmark for electrochemical thermal switches.
Hiromichi Ohta, Professor, Research Institute for Electronic Science, Hokkaido University
Hiromichi Ohta explained, “The thermal conductivity in its minimal state (off-state) is 2.2 W/m·K, but in the oxidized state (on-state), it significantly rises to 12.5 W/m·K. These performance metrics remain consistent after 100 cycles of reduction and oxidation, demonstrating remarkable durability and reliability for extended usage in practical applications.”
One of the key advantages of this innovative technology is its reliance on cerium oxide, a material that is both abundant and cost-effective. Recognized for its economic and ecological benefits, CeO2 stands out as a sustainable alternative to the rare and expensive materials typically used in conventional thermal switches. This not only reduces costs but also minimizes the environmental impact of heat management systems, making the technology more scalable and adaptable across various industries.
The creation of CeO2-based thermal switches marks a major breakthrough in thermal management. With wide-ranging applications in fields like electronics cooling and renewable energy systems, these devices are anticipated to revolutionize the way heat is controlled. Whether regulating infrared heat transfer in thermal shutters and advanced displays or improving waste heat recovery, these switches contribute to the development of more energy-efficient and sustainable solutions.
Journal Reference:
Jeong, A., et al. (2024) High-performance solid-state electrochemical thermal switches with earth-abundant cerium oxide. Science Advances. doi/10.1126/sciadv.ads6137