Materials that convert heat directly into electricity have been useful for some niche applications, like powering deep-space probes. But they’ve been too expensive and inefficient for their potential killer app: harvesting immense amounts of energy from the waste heat generated by power plants and cars. Now researchers at the University of California, Berkeley, have shown that a cheap organic material can make electricity from heat, potentially opening the way to affordable “thermoelectrics.”
The researchers trapped a few organic molecules between a sheet of gold and the ultrasharp gold tip of a scanning tunneling microscope. They heated the gold surface and used the microscope tip to measure the voltage created by the junction of molecule and metal. A large-scale heat-conversion system will require a process for arranging multiple layers of such junctions between two sheets of metal, one for applying heat and the other for harvesting electricity.
Become an MIT Technology Review Insider for in-depth analysis and unparalleled perspective.Subscribe today