A recent study1 by Dr. Fabian Garmroudi and a team of international researchers opens the door for one of the most significant advancements in thermoelectric technology in decades. The paper delves into the team’s study of various materials and how it led them to successfully enhance thermal and electrical decoupling. Here’s what you need to know.
How Thermoelectric Materials Transfer Heat
Thermoelectrics are unique compared to other forms of matter. In the traditional sense, heat energy is transferred via mobile charge carriers and by vibrations of the atoms in the crystal lattice. The latter represents when atoms vibrate against each other using the same phase relationship.
Notably, materials that can transfer heat quickly are called conductors. Metal is an excellent example of a heat conductor. If you heat a metal rod and place it next to another piece of metal, the charged atoms and lattice vibrations will quickly transfer some of the energy to the other piece. Notably, pure diamond is the material noted to have the highest thermal conductivity.
What Are Thermoelectric Materials and How Do They Work?
Thermoelectric materials differ from traditional materials in that they are good at conducting electricity but not at conducting heat. Since these items are poor at transferring heat energy, they make the perfect thermal insulator.
The main way that thermoelectric material accomplishes this task is by attempting to decouple charge and heat transport. Today, these materials play a vital role in advanced electronics, cooling, and industrial applications.
The History of Thermoelectric Technology: From Seebeck to Today
The journey to super-fast chilling, freezing, and high-end electronics has many starting points. In 1821, Thomas Johann Seebeck made a startling discovery. He noted that certain metals generate an electric current when they have temperature differences and are brought near each other.
This discovery led to Jean Charles Athanase Peltier demonstrating that this effect could result in both heating and cooling depending on the setup. This revelation opened the door for today’s advanced thermoelectric materials and manufacturing processes.
Modern Thermoelectric Materials: Current Industry Standard
Today’s most commonly used thermoelectric material is a grey powder called bismuth telluride, Bi2Te3. This chemical was created in the 1950s and has remained the industry standard for the last +70 years. Today, Bi2Te3-based systems are the only commercially available option.
Challenges Facing Thermoelectric Materials Today
This scenario has led to some slowdowns in innovations. For one, tellurium is a rare mineral that is difficult and expensive to obtain. Additionally, these materials are fragile. Their brittle nature can result in easily damaged components.
How Thermoelectric Materials Are Made: Manufacturing Challenges
Another major drawback to this approach is that it’s expensive. The sophisticated methods required to design and manufacture thermoelectric materials with extremely low thermal conductivity remain a hindrance to further adoption.
Solving the Electrical Transfer Problem in Thermoelectrics
One of the main issues was that all previous efforts that involved inhibiting lattice-driven heat transport reduced carrier mobility. As such, the efforts were futile until recently. Now, a team of creative researchers believes they have unlocked the key to suppressing lattice vibrations without reducing electrical transfer.
Breakthrough Thermoelectrics Study: Decoupling Heat and Charge
The “Decoupled charge and heat transport in Fe2VAl composite thermoelectrics with topological-insulating grain boundary networks” study, published in the journal Nature Communications, introduces hybrid materials, a new manufacturing process, and a revolutionary design to achieve thermal and electrical decoupling.
The team took a different approach than their predecessors in that they sought to integrate chemically and structurally distinct Bi1−xSbx as a secondary phase between Heusler grains. The process utilizes a process called liquid-phase sintering to integrate the archetypal topological insulator Bi1−xSbx between Fe2V0.95Ta0.1Al0.95 grains.
Source – Nature Communications
This approach avoids the traditional tradeoff where attempts to reduce heat transfer also harm electrical mobility.
Hybrid Thermoelectric Materials Using Multiphase Composites
At the core of the study is the creation of hybrid materials. These multiphase composites are ideal for the task because they provide different mechanical properties but operate similarly when discussing electronic properties. The first material (Fe2V0.95Ta0.1Al0.95) combines powder of an alloy of iron, vanadium, tantalum, and aluminum.
The second material (Bi0.9Sb0.1) in the mixture consists of powder of bismuth and antimony. This structure creates a topological insulator phase. A topological insulator phase is a unique class of quantum materials. They have the ability to insulate internally while providing loss-free charge on their surface.
How Temperature Affects Thermoelectric Composite Performance
The start of the process began with the materials being heated up in an induction melting furnace. This allowed the materials to be synthesized and ground into a powder. The scientist ground the powder and then mixed the two materials again while sintering at 1373 K. This step caused the Bi0.9Sb0.1 to melt and coat the grains.
This scenario creates a grain boundary phase, which is ideal for the researcher’s findings. Notably, the materials don’t mix on an atomic level. Instead, the BiSb material is deposited at the micrometer-sized interfaces between the crystals of the FeVTaAl alloy, creating a hard thermoelectric material with some impressive capabilities.
Disrupting Lattice Vibrations to Reduce Heat Transfer
One of the main things the researchers noticed was that the new material had very different lattice structures from the other materials. The differences in these layers were so stark that the thermal vibrations couldn’t transfer across the crystal lattice effectively. This design effectively reduces thermal vibrations across the entire surface.
Boosting Electrical Mobility in Thermoelectric Materials
The team also noted that there was an increase in charge carriers. Since both materials have similar charge carrier characteristics, there was no loss detected. Interestingly, a gain in performance was unexpectedly recorded, signalling that the material has excellent thermoelectric properties.
Testing the Performance of New Thermoelectric Materials
The design phase of the study was conducted at the National Institute for Materials Science in Japan. The team conducted several in-depth tests, including structural investigations, to determine how the new design could hold up in different scenarios.
The team also registered extensive thermoelectric and magneto-transport measurements as part of the research. They determined that modifications in the microstructure affected the Hall effect in a broad temperature and magnetic field range.
Results: Improved Thermoelectric Efficiency and Stability
The test proved that the material had exceptional thermoelectric properties. It successfully reduced lattice thermal conductivity across the board. Also, it enhanced carrier mobility. These accomplishments were due to the design that incorporated topologically protected charge transport along the grain boundaries.
The engineers also registered a performance boost and more efficiency from their new design. It proved that certain materials enable engineers to target heat transport without degrading charge transport. Notably, the performance of the device surpassed previous attempts by 100%.
Key Benefits of the New Thermoelectric Technology
There are many benefits that this study brings to the market. For one, it utilizes readily available earth-abundant materials. This approach opens the door for more research and studies to be conducted.
It also helps to keep costs in line while demonstrating how the material could be scaled up to meet future needs. Thermoelectrics have been notoriously difficult to manufacture and delicate. This new option is both more resilient and offers lower entry costs compared to the industry standards.
Material Stability and Recyclability of Thermoelectrics
Another major benefit of this study is that it introduces a method to achieve thermoelectrics without leaving lasting waste. This approach has great recyclability, as all the materials are earth-abundant and were compiled in a way that does not create large amounts of environmental pollution.
Real-World Applications of Thermoelectrics and Commercial Timeline
There are endless applications for this technology. Thermoelectrics are seen by many as one of the best ways for the world to achieve its net-zero carbon goals and create a more sustainable existence. Keenly, this discovery opens the door for the creation of autonomous energy supplies. Here are some other vital applications for this tech.
Thermoelectrics and the Internet of Things (IoT)
The Internet of Things includes billions of smart devices globally. This massive network of sensors could utilize this study to create self-sustaining energy sources. This capability would enable the Internet of Things to take a step forward in terms of adoption and usability.
Thermoelectric Materials in Space Exploration and Satellites
Thermoelectrics are a primary way in which future space explorers will keep their lights on. These systems will be able to take the extreme heat or cold found in space and transfer it into power that can be used to travel, protect, and enhance the lives of future space explorers.
Using Thermoelectrics in Sustainable Smart Homes
Thermoelectrics could help power your home in the future. Imagine your house staying cool when it gets hot outside without the need to power AC units or fans. Builders continue to see these materials as a way to create more sustainable homes that require a lot less energy to operate.
When Will Thermoelectric Materials Become Mainstream?
It could be +5 years before this technology makes its way into the market. The science is there, but the sheer size of the industry and the need to explore even more options could mean that this tech still has some years of research before the engineers feel like they’ve optimized it to the point that it’s commercially viable.
Thermoelectrics Researchers
An international team of researchers led by Fabian Garmroudi made the thermoelectrics study possible. The study was supported by a variety of respected educational institutions, including the Los Alamos National Laboratory (USA). Additionally, the team developed the new hybrid materials at the National Institute for Materials Science in Japan. Financial support for the project was obtained through the Lions Award as well.
The Future of Thermoelectric Technology
The future of thermoelectrics is bright. The team behind this study now wants to focus on developing a thermoelectric material that can compete with commercially available compounds based on bismuth telluride. They noted that they intend to research other topological insulators like Bi2Se3.
Investing in the Thermo Electronics Sector
Many firms are competing in the thermoelectrics sector for dominance. This market continues to see growing demand as computing power and travel needs increase. These firms have put significant effort into exploring thermoelectrics and other green energy options. Here’s one company ideally positioned to benefit from the latest thermoelectrics study.
TTM Technologies Inc. (TTMI +3.16%) entered the market in 1998. It was founded by Kent Alder and originally launched in Washington. In 1999, the firm began acquiring competitors. The acquisition of Pacific Circuits, Inc. led the company to shift operations to California.
Today, TTM Tech is a leading PCB board manufacturer. Notably, it is the largest in North America and is the main supplier of boards to the US military. It currently has +16,400 employees and has seen a considerable increase in work volume over the last year.
TTM Technologies, Inc. (TTMI +3.16%)
Interestingly, TTMI stock has strong support from some of the largest investment firms in the world. For example, BlackRock owns around 17% of the company’s stock, equalling 18,299,780 shares. These factors, coupled with the company’s history of innovation, make TTMI a solid stock to watch.
Latest News on TTM Technologies
Thermoelectrics: The Next Cool Tech in Energy Conversion
The thermoelectrics movement is in full swing, and this latest development is sure to inspire further innovation. These unique materials are crucial to expanding man’s reach and understanding. Consequently, they will continue to play a vital role in future technologies that require heat mitigation.
Learn about other cool energy projects now.
Studies Referenced:
1. Garmroudi, F., Serhiienko, I., Parzer, M., Ghosh, S., Ziolkowski, P., Oppitz, G., Nguyen, H. D., Bourgès, C., Hattori, Y., Riss, A., Steyrer, S., Rogl, G., Rogl, P., Schafler, E., Kawamoto, N., Müller, E., Bauer, E., de Boor, J., & Mori, T. (2025). Decoupled charge and heat transport in Fe₂VAl composite thermoelectrics with topological-insulating grain boundary networks. Nature Communications, 16(2976). https://doi.org/10.1038/s41467-025-57250-6