Thermoelectrics directly convert heat into electricity and power a wide array of items, from NASA’s Perseverance rover currently exploring Mars to travel coolers that chill beverages.
A material’s atomic structure, which is how atoms arrange themselves in space and time, determines its properties. Typically, solids are crystalline or amorphous. In crystals, atoms are in an orderly and symmetrical pattern. Amorphous materials have randomly distributed atoms. Researchers have created a new hybrid compound in which the crystalline and amorphous sublattices are intertwined into a crystal-amorphic duality.
The material is a unique hybrid atomic structure with half being crystalline and half amorphous. The researchers created the hybrid material by intentionally mixing elements in the same group on the periodic table but with different atomic sizes. They used the atomic size mismatches between sulfur and tellurium and between copper and silver to create a new compound (Cu1-xAgx)2 (Te1-ySy) in which the crystalline and amorphous sublattices intertwine into the crystal-amorphicity duality.
The new compound exhibited excellent thermoelectric performance but more important than that is how it achieves that level of performance. Traditionally, thermoelectric materials are crystals; however, the new material is not pure crystal but it can achieve the same level of performance.