According to Science Daily,
Engineering researchers at Rensselaer Polytechnic Institute (RPI) have developed a new method for creating advanced nanomaterials that could lead to highly efficient refrigerators and cooling systems requiring no refrigerants and no moving parts. The key ingredients for this innovation are a dash of nanoscale sulfur and a normal, everyday microwave oven.
Here’s a video of Rensselaer Professor Ganpati Ramanath, a faculty member in the Department of Materials Science and Engineering at Rensselaer, explaining the technology and some of its possible applications.