New production method reduces costs and material loss

Thermoelectric materials play a central role in energy generation and cooling by converting temperature differences into electrical energy or transporting heat in a targeted manner. However, one challenge of this technology lies in the cost-intensive production and limited efficiency of the materials. Researchers at the Institute of Science and Technology Austria (ISTA) have now developed a new 3D printing technique that can be used to produce high-performance thermoelectric materials more cost-effectively and with less material loss. The results have been published in the journal Science.

Thermoelectric converters are used in electronics cooling because they can transport heat without moving parts. Conventional manufacturing methods rely on solid blocks of material that are shaped using complex processes. This not only leads to high production costs, but also to considerable material losses. The ISTA researchers, led by Maria Ibáñez, have developed an alternative method in which thermoelectric materials are produced directly in the desired shape using 3D printing. Shengduo Xu, postdoc at ISTA, emphasizes: “Our innovative integration of 3D printing in the production of thermoelectric coolers significantly improves manufacturing efficiency and reduces costs.”

In addition to additive manufacturing, the composition of the printing inks used plays a decisive role. When the carrier solvent evaporates, stable atomic bonds are formed between the material grains, which optimizes the electrical conductivity. Through this targeted adaptation of the material structure, the researchers were able to raise the performance of the printed thermoelectric coolers to a commercially competitive level.

ISTA Professor Ibáñez explains: “With performance at a commercially-competitive level, our work has the potential to go beyond academic research, gaining practical relevance and attracting interest from industries seeking real-world applications.”

The new method could have applications beyond electronics cooling. For example, thermoelectric coolers could be used in medicine to treat burns or muscle tension. The approach also opens up possibilities for generating energy through the use of waste heat, for example in industrial processes or in vehicles.

“With our current work, we can print thermoelectric materials in 3D exactly in the required shape. What’s more, the resulting devices have a net cooling effect of 50 degrees in the air. This means that our 3D-printed materials perform similarly to those that are significantly more expensive to produce,” says Xu.

“We used an extrusion-based 3D printing technique and designed the ink formulation to ensure the integrity of the printed structure and increase particle bonding. This allowed us to produce the first thermoelectric coolers made of printed materials that have comparable performance to ingot-based devices while saving material and energy,” says Ibáñez.

The researchers see their work as an important step towards the sustainable and economical production of thermoelectric devices. “We have successfully implemented a full-cycle approach, from optimizing the thermoelectric performance of the raw materials to producing a stable, high-performance end product,” says Ibáñez. Xu adds: “Our work offers a transformative solution for the production of thermoelectric devices and heralds a new era of efficient and sustainable thermoelectric technologies.”