Simultaneous Determination of Seebeck Coefficient and Electrical Conductivity

The optimization of energy efficiency is an important issue in the 21st century. In many industrial applications (melting furnaces, drying plants, incineration plants, power plants, etc.), a high amount of heat energy remains unused. Waste heat is also generated in many other areas – from automobiles to day-to-day life.

The conversion of this waste heat into electrical power is one of the most important challenges in the field of thermoelectrics. Such results are achieved by means of thermoelectric generators, the effectiveness of which depends significantly on the quality of the thermoelectric material.
 
To develop suitable materials, it is essential to have knowledge about the thermophysical properties which describe the efficiency (ZT value, figure of merit) of the materials, as follows:

S = Seebeck coefficient or thermoelectric potential of the material [µV/K]

σ = electrical conductivity of the material [S/cm]

λ = total thermal conductivity of the material [W/(m·K)]

T = absolute temperature


In order to be deemed suitable, thermoelectric materials should be characterized by high electrical conductivity, a large Seebeck coefficient and low thermal conductivity. The extent to which it will be possible to use thermoelectric generators in the future will depend upon the performance of the materials.

Effective immediately, NETZSCH is offering the SBA 458 Nemesis, with which the Seebeck coefficient and electrical conductivity can be measured simultaneously.

Instruments for the determination of thermal conductivity, thermal diffusivity, cp determination and density are also included in the NETZSCH product range. NETZSCH thus offers a complete solution for determining the ZT value.

SBA 458 Nemesis®

Thermoelectric materials should possess high working temperatures and optimized efficiency. The relative performance is described by the figure of merit (ZT). It highlights the importance of the Seebeck coefficient with respect to the performance. The SBA 458 Nemesis® allows for simultaneous measurement of the Seebeck coefficient and electrical conductivity under indentical conditions.