Exploring an area overlooked by other scientists, physicists at the Florida State University-

headquartered  National High  Magnetic  Field Laboratory have discovered that a class of 

materials  called  "1-2-20s" have  very  promising  thermoelectric  properties, opening the 

floodgates for further research into these fascinating materials.

The study was published in Science Advances.

Thermoelectric devices can produce electricity if there is a temperature difference between 

the two ends. They can also do the opposite: use electricity to absorb or release heat. This 

property has many potential applications, from compressor-free refrigeration to power 

generation in space to recouping all the energy wasted by car engines (about 40 percent) that 

escapes through heat.

"It's not free energy," said MagLab physicist Ryan Baumbach, corresponding author on the 

paper, "but it's the next best thing."

Most materials have very little thermoelectric effect. That's because the transfer of electricity 

across a material and the transfer of heat usually go hand in hand. In general, nature wants to 

keep heat and electrical conductivity linked, but to have good thermoelectric performance, 

these two properties need to be decoupled.

About  two  years  ago,  Baumbach  suggested  that  Kaya  Wei,  the  MagLab's Jack Crow 

postdoctoral fellow and a member of Baumbach's research group, study a "1-2-20" material 

that seemed like a good candidate for thermoelectricity.

The specific material Baumbach proposed featured three basic ingredients in a "1-2-20" ratio: 

the element ytterbium; a transition metal (either cobalt, rhodium or iridium); and the element 

zinc. Baumbach had a hunch this compound had what it takes, if manipulated properly in his 

lab, to thumb its nose at nature and unlink thermal conductivity from heat conductivity.

Using high-temperature furnaces in Baumbach's lab, Wei synthesized the compound in crystal 

form and subjected the samples to a gauntlet of measurements. The results confirmed that, at 

low temperatures, the material was in fact a promising thermoelectric material.