The Need

Thermoelectric effects enable direct conversion of thermal to electrical energy, which provides an alternative power generation and temperature conditioning. Although thermoelectric systems are environmentally friendly, the efficiency of thermoelectric devices cannot compete with current gold-standard conversion methods, such as the Carnot Cycle. There is an unmet need for an improved thermoelectric figure of merit and optimization of thermoelectric materials via porosity.

The Technology

Researchers at The Ohio State University, led by Dr. Joseph Heremans, have developed a formulation to increase efficiency of materials used in thermoelectric energy converters. By creating porous materials with an optimum density range on the order of 80% of the theoretical density of fully massive metal, the thermoelectric figure of merit can be improved by scattering more phonons than electrons.

Commercial Applications

• Solid State Thermoelectrics
• Solid State Electrical Power Generation
• Materials Manufacturing

Benefits/ Advantages

• Increases the efficiency of materials used in thermoelectric energy converters
• Porous thermoelectric materials also apply to lowering lattice thermal conductivity of certain alloys
• The effect of introducing porosity in n-type alloys is the same as in specific p-type alloys regardless if the pores are open or closed
• zT greater than 1.2 at room temperature