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RESEARCHERS have created a new range of advanced nanomaterials that they say could lead to highly efficient next-generation cooling systems.

The team, from the Rensselaer Polytechnic Institute, US, says its technique involves doping thermoelectric materials – able to control their temperature using electricity – with a “dash” of nanoscale sulphur. Though thermoelectric refrigerators have been in use for more than 20 years, they have always been plagued by high costs and low inefficiencies, something that may soon be changing.

“This is not a one-off discovery,” says Ganpati Ramanath, an engineering professor at Rensselaer. “Rather, we have developed and demonstrated a new way to create a whole new class of doped thermoelectric materials with superior properties. Our findings truly hold the potential to transform the technology landscape of refrigeration and make a real impact on our lives.”

Ramanath and his team doped the thermoelectric material – intentionally contaminating its structure with tiny amounts of sulphur – using nothing more than a run-of-the-mill microwave oven. This produced a powder that could be formed into small pellets. The scientists claim that their process not only produces materials of significantly higher quality than existing methods, but is much faster, cheaper and easier to scale-up.

“It’s really amazing as to how nanostructures seasoned with just a few atoms of sulphur can lead to such superior thermoelectric properties, and allows us to reap the benefits of nanostructuring on a macroscale,” Ramanath says.

As well traditional roles in refrigerators and air conditioners, the Rensselaer researchers say their technology could be used to cool computer chips, and have created a spin-off company named ThermoAura to commercialise the work.

Nature Materials, doi:10.1038/NMAT3213