Apr 19 2021
Thermoelectrics power an extensive range of items by directly converting heat into electricity—spanning from NASA’s Perseverance rover now exploring Mars to travel coolers that chill beverages.
Jian He is an associate professor in the College of Science’s Department of Physics and Astronomy. Image Credit: Clemson University.
A physicist from Clemson University has joined hands with collaborators from China and Denmark to make a new and possibly paradigm-shifting high performance thermoelectric compound.
The atomic structure of the material, the way atoms tend to arrange themselves in time and space, governs its properties. Solids are generally amorphous or crystalline in nature.
In crystals, atoms are arranged in a symmetrical and orderly pattern. Amorphous materials exhibit randomly distributed atoms.
Jian He, a Clemson University researcher, together with his international group has made a new hybrid compound where the amorphous and crystalline sublattices are interlaced into a unique crystal-amorphic duality.
Our material is a unique hybrid atomic structure with half being crystalline and half amorphous. If you have a unique or peculiar atomic structure, you would expect to see very unusual properties because properties follow structure.
Jian He, Associate Professor, Department of Physics and Astronomy, College of Science, Clemson University
The study results were published online in Joule, a high profile energy research journal, in a paper titled “Thermoelectric materials with crystal-amorphicity duality induced by large atomic size mismatch,” on April 16th, 2021, ahead of the May 19th issue.
New Hybrid
The team made the hybrid material by purposefully combining elements in the same group present on the periodic table but with various atomic sizes.
In this context, they utilized the atomic size discrepancies between tellurium and sulfur and between silver and copper to make a new compound (Cu1-xAgx)2(Te1-ySy) in which the amorphous and crystalline sublattices interlace into a unique crystal-amorphicity duality. The new compound showed superior thermoelectric performance.
Although this breakthrough does not directly have any application at present, it could probably result in improved thermoelectrics in the future.
The new material performs well, but more important than that is how it achieves that level of performance. Traditionally, thermoelectric materials are crystals. Our material is not pure crystal, and we show we can achieve the same level of performance with a material with a new atomic structure.
Jian He, Associate Professor, Department of Physics and Astronomy, College of Science, Clemson University
He stated that he anticipates that the new material will start impacting applications in the next one or two decades.
They definitely can do something current thermoelectric materials cannot do, but not now. However, the future of this research is bright.
Jian He, Associate Professor, Department of Physics and Astronomy, College of Science, Clemson University
Apart from He, the study involved researchers from Shanghai Jiaotong University, Shanghai Institute of Ceramics and SUSTech in China, and Aarhus University in Denmark.
Journal Reference:
Zhao, K., et al. (2021) Thermoelectric materials with crystal-amorphicity duality induced by large atomic size mismatch. Joule. doi.org/10.1016/j.joule.2021.03.012.