1713533
9781558996274
This volume, the fifth in a popular series from the Materials Research Society, provides a benchmark for the current state in the field of thermoelectric materials research and development. Highlights of the volume include results on superlattices thai show a ZT = 2.4 at room temperature in p-type Bi2Te3/Sb2Te3 superlattice thermoelectrics. This represents a greater than two-fold improvement in ZT as compared to the best materials presently in use. For n-type super-lattices, ZT = 1.2 at room temperature were achieved. In addition, preliminary results on p-n couple devices from these superlattices indicate fast-acting spot cooling in addition to improved performance. Thermoelectric materials are utilized in a wide variety of applications related to solid-state refrigeration or small-scale power generation. Despite the extensive investigation of traditional thermo-electric materials (alloys based on Bi2Te3 for refrigeration and Si(1-x)Gex for power generation) there is still substantial room forimprovement, and thus, entirely new classes of compounds will have to be investigated. The volume focuses on these new materials as well as developments in device engineering. And finally, the essence of a good thermoelectric is given by the determination of the material's figure of merit, Z = S2s/l, where S is the Seebeck coefficient, s the electrical conductivity and l the thermal conductivity. Many papers presented here revolve around either maximizing the numerator of Z, called the power factor, or by minimizing l. The best thermoelectric materials presently in use have a maximum value of ZT = 1, the upper limit for more than 30 years. However, due to new methods of materials synthesis andcharacterization that are now available, this "upper limit" may soon become irrelevant.Nolas, G. S. is the author of 'Thermoelectric Materials 2001 - Research and Applications Materials Research Society Symposium Proceedings' with ISBN 9781558996274 and ISBN 1558996273.
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