Engineering researchers at Rensselaer Polytechnic Institute have developed a new method for creating advanced nano-materials that could lead to super-efficient refrigerators and cooling systems requiring no refrigerants and no moving parts.

The key ingredients for this innovation are a dash of nano-scale sulfur and a normal, everyday microwave oven.

At the heart of solid-state cooling systems are thermoelectric materials, which can convert electricity into a range of different temperatures - from hot to cold.

Thermoelectric refrigerators based on these principles have been available for more than 20 years, but they are still small and highly inefficient.

This is largely because the materials used in current thermoelectric cooling devices are expensive, difficult to make in large quantities, and lack the necessary combination of thermal and electrical properties.

However, a new study recently published in the journal Nature Materials describes a solution that overcomes all of these challenges and opens the door to a new generation of high-performance, cost effective solid-state refrigeration and air conditioning.

Driving this research breakthrough is the idea of doping nano-structured thermoelectric materials with tiny amounts of sulfur.

The researchers at the Rensselaer Nanotechnology Center produced the doped materials by cooking the material and the dopant together for a few minutes in a store-bought $40 microwave oven.

The resulting powder was formed into pea sized pellets by applying heat and pressure in a way that preserved the properties endowed by the nano-structuring and the doping.

And, ironically these inexpensive pellets exhibit properties better than those of the hard-to-make thermo-electric materials currently available in the marketplace.

Additionally, this new method for creating the doped pellets is much faster, easier, and cheaper than conventional methods of making thermoelectric materials.

More importantly, this is not a one-off discovery. Rather, it represents a new way to create a whole new class of doped thermo-electric materials with superior properties.

These findings truly hold the potential to transform the technology landscape of refrigeration and make a real impact on our lives.

Beyond refrigerators and air conditioning, the researchers envision this technology one day being used to cool computer chips.