Measurement and Characterization Techniques for Thermoelectric Materials

1997 ◽  
Vol 478 ◽  
Author(s):  
Terry M. Tritt

AbstractCharacterization of thermoelectric materials can pose many problems. A temperature difference can be established across these materials as an electrical current is passed due to the Peltier effect. The thermopower of these materials is quite large and thus large thermal voltages can contribute to many of the measurements necessary to investigate these materials. This paper will discuss the characterization techniques necessary to investigate these materials and provide an overview of some of the potential systematic errors which can arise. It will also discuss some of the corrections one needs to consider. This should provide an introduction to the characterization and measurement of thermoelectric materials and provide references for a more in depth discussion of the concepts. It should also serve as an indication of the care that must be taken while working with thermoelectric materials.

2015 ◽  
Vol 1107 ◽  
pp. 716-721 ◽  
Author(s):  
Nadhrah Md Yatim ◽  
Gao Min

The thermoelectric dimensionless figure-of-merit, ZT, which consists of the Seebeck coefficient, α, electrical resistivity, ρ and thermal conductivity, λ, is an important parameter that characterizes the energy conversion performance of thermoelectric materials and devices. Current techniques for determining ZT involve measurements these three properties individually or ZT directly, but all techniques are carried out under a small temperature difference (ΔT). In reality, a thermoelectric device generally operates under a much larger ΔT and with an electrical current flowing through the thermoelectric materials. A novel principle for ZT measurement has been proposed, which has the capability of measuring ZT values under a large ΔT and with an electrical current flowing through the samples. Although this technique has been proof experimentally using thermoelectric module, its implementation on thermoelement has proved to be very challenging due to low electrical resistance of the samples. In this paper, newly develop apparatus with a modified operating principle was proposed and carried out. The performance of this system was investigated using a standard n-type Bi2Te3sample. The results show that the system has a repeatability of <10% and an accuracy of 13-32%. Investigation on single materials structures showed that there were noticeable differences between a small and a large ΔT, which can be attributed to the Thomson effect and changes in ρλ values.


Author(s):  
Sweta Pendyala ◽  
Dave Albert ◽  
Katherine Hawkins ◽  
Michael Tenney

Abstract Resistive gate defects are unusual and difficult to detect with conventional techniques [1] especially on advanced devices manufactured with deep submicron SOI technologies. An advanced localization technique such as Scanning Capacitance Imaging is essential for localizing these defects, which can be followed by DC probing, dC/dV, CV (Capacitance-Voltage) measurements to completely characterize the defect. This paper presents a case study demonstrating this work flow of characterization techniques.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3154
Author(s):  
Kony Chatterjee ◽  
Tushar K. Ghosh

Since prehistoric times, textiles have served an important role–providing necessary protection and comfort. Recently, the rise of electronic textiles (e-textiles) as part of the larger efforts to develop smart textiles, has paved the way for enhancing textile functionalities including sensing, energy harvesting, and active heating and cooling. Recent attention has focused on the integration of thermoelectric (TE) functionalities into textiles—making fabrics capable of either converting body heating into electricity (Seebeck effect) or conversely using electricity to provide next-to-skin heating/cooling (Peltier effect). Various TE materials have been explored, classified broadly into (i) inorganic, (ii) organic, and (iii) hybrid organic-inorganic. TE figure-of-merit (ZT) is commonly used to correlate Seebeck coefficient, electrical and thermal conductivity. For textiles, it is important to think of appropriate materials not just in terms of ZT, but also whether they are flexible, conformable, and easily processable. Commercial TEs usually compromise rigid, sometimes toxic, inorganic materials such as bismuth and lead. For textiles, organic and hybrid TE materials are more appropriate. Carbon-based TE materials have been especially attractive since graphene and carbon nanotubes have excellent transport properties with easy modifications to create TE materials with high ZT and textile compatibility. This review focuses on flexible TE materials and their integration into textiles.


2013 ◽  
Vol 42 (7) ◽  
pp. 1956-1959 ◽  
Author(s):  
S. Battiston ◽  
S. Fiameni ◽  
M. Saleemi ◽  
S. Boldrini ◽  
A. Famengo ◽  
...  

1983 ◽  
Vol 61 (2) ◽  
pp. 301-304 ◽  
Author(s):  
Jacques Bures ◽  
François Leonard ◽  
Jean-Pierre Monchalin

A self-scanned photodiode array has been used as a multiplex sensor for laboratory detection and measurement, by dispersive spectroscopy, of trace quantities of the atmospheric pollutant NO2. The on-line data acquisition and numerical analysis system allows in particular to eliminate some systematic errors and drifts (Taylor filtering) and the noise associated with high spatial frequencies (low-pass filtering). We have then been able to show that an absorption spectrum, corresponding to low absorber concentrations, has a sufficient information content for the characterization of the pollutant and the measurement of its concentration (ppm m), even when noise and drifts are present. The proposed system can be favorably compared to the ones, based on a single photoelectric detector, which are commercially used.


1998 ◽  
Vol 545 ◽  
Author(s):  
Y. Shinohara ◽  
Y. Imai ◽  
Y. Isoda ◽  
I. A. Nishida

AbstractThe Harman method was applied to measure thermal conductivity κ of thermoelectric materials, and the reliability of the measured κ was investigated. The quantitative κ requires a highly sensitive technique to measure minute Peltier heat. Temperature difference by Peltier heat pumping was successfully measured by developing the DC method of resistance measurement. κ of n-type Bi2Te3 sintered compact and n-type PbTe boules was measured at 295K by the Harman method. Static comparative method was also applied to obtain the standard value of κ. In the case of Bi2Te3, the κ by the Harman method agreed well with the standard value. In the case of PbTe in the electron concentration ne range <5 × 1024/m3, the κ almost agreed with the standard value. However, PbTe in the ne range ≥1 × 1025/m3 showed a larger κ than the standard value. The Harman method has an error to give the larger κ for the material with a large carrier component κ, of κ This error is due to the fast conduction of Peltier heat by the carrier. The reliable κ can be measured for the material with a small κ,.


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