Instrument for simultaneous measurement of Seebeck coefficient and thermal conductivity in the temperature range 300–800 K with Python interfacing

Abstract

Fabrication and characterization of an instrument for the high-temperature simultaneous measurement of the Seebeck coefficient ( S) and thermal conductivity ( κ) have been carried out with Python automation. The steady-state-based Fourier’s law of thermal conduction is employed for κ measurement. The parallel thermal conductance technique is implemented for heat loss measurement. Introducing a thin heater and insulating heater base minimizes the heat loss and makes it easier to arrive at high temperatures. Measurement of S is carried out using the differential method. The same thermocouples are used to measure the temperature as well as voltage for S measurement. Care of temperature dependent S of the thermocouple has also been taken. Simple design, small size, and lightweight make this instrument more robust. All the components for making a sample holder are easily available in the market and can be replaced as per the user’s demand. This instrument can measure samples with various dimensions and shapes in the temperature range 300–800 K. The instrument is validated using different classes of samples, such as nickel, gadolinium, Fe2VAl, and LaCoO3. A wide range of S values from ∼−20 to ∼600 μV/K and κ values from ∼1.1 to ∼23.5 W/m K are studied. The measured values of S and κ are in good agreement with the reported data.

Enhancement in thermoelectric performance of hydrothermally synthesized Ca and Sb co-doped Bi2Te3 nanostructures

“…The rectangular shape pellets with dimension of 6 mm × 3 mm × 1 mm were cut for the measurement of electrical conductivity. The Seebeck coefficient (S) and thermal conductivity (k) were measured simultaneously with S -k measurement setup in the temperature range of 300 K to 480 K under a vacuum level of ∼ 10 −3 bar [41]. The four-probe dc method was used to measure the electrical conductivity under the vacuum of ∼ 10 −3 bar.…”

Improvement in thermoelectric properties of Zn–Mn co-doped nanostructured SnTe through band engineering and chemical bond softening

“…The electrical resistivity as a function of temperature was determined using a resistivity measurement setup. Home-made Sκ measurement set-up was used to simultaneously record the Seebeck coefficient (S) and thermal conductivity (κ T ) at temperatures between 300 K and 473 K under 10 −3 bar vacuum level [29].…”

“…This means that the minimum κ L in Sn 0.89 Mn 0.09 Zn 0.02 Te is only about 50% that of pure SnTe. Further, the relatively smaller size of grains in doped samples can cause more phonon scattering resulting in lower κ L in Sn 0.89 Mn 0.09 Zn 0.02 Te [29]. Point defects created by elemental substitution may reduce the lattice thermal conductivity as the doping concentration rises (see figure 8(a)) [30,31] softening of chemical bonds following Zn-Mn co-doping may reduce phonon group velocity, which can significantly decrease the lattice thermal conductivity of SnTe (see figure 8(b)) [6,18,39].…”

Thermoelectric properties of Fe$_{2}$VAl at high temperature region: A combined experimental and theoretical study

“…The room temperature x-ray diffraction confirms the L2 1 phase of face-centered cubic structure with lattice parameters 5.76 Å, consistent with the literature 36 . The measurements of Seebeck coefficient and thermal conductivity were performed in the temperature range of 300 − 800 K using home-made experimental setup 37 . The resistivity was measured in the temperature range 300 − 720 K using the in-house instrumental setup 38 .…”