Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.4
2.9
Journals
Metals
Special Issues
Thermoelectric Compounds: Processing, Properties and Applications
share announcement

Thermoelectric Compounds: Processing, Properties and Applications

A special issue of Metals (ISSN 2075-4701).

Deadline for manuscript submissions: closed (30 April 2020) | Viewed by 16347

Special Issue Editor

Dr. Alberto Castellero

E-Mail Website
Guest Editor
Department of Chemistry, University of Turin, Torino, Italy
Interests: thermoelectric materials for waste heat recovery; non equilibrium processing; thermodynamics and kinetics of metastable phases

Special Issue Information

Dear Colleagues,

Thermoelectric compounds are an exciting category of materials that can convert a temperature gradient into electricity through the Seebeck effect. Thus, thermoelectric technology is promising for improving energy efficiency in environments where waste heat is produced (e.g. industrial processes, automotive exhaust, wearable items).
Thermoelectric efficiency depends, on the one hand, on the transport properties of the materials through the dimensionless figure of merit ZT = S2σT/k (where S is the Seebeck coefficient, σ is the electrical conductivity, k is the thermal conductivity and T is the absolute temperature) and, on the other hand, on the boundary conditions (i.e. temperature gradient).

The maximization of thermoelectric properties passes through the development of new materials and the optimization of the existing ones by means of reliable and affordable processing routes.

This Special Issue will focus on

  • the relationship between processing and properties of thermoelectric materials;
  • the development of new thermoelectric compounds;
  • case studies of thermoelectric applications.

It is my pleasure to invite you to submit a manuscript for this Special Issue. Full papers, communications, and reviews are all welcome.

Dr. Alberto Castellero
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Metals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Thermoelectric compounds
  • Thermoelectric materials development
  • Thermoelectric materials processing
  • Thermoelectric properties
  • Thermoelectric applications

Published Papers (6 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

13 pages, 4460 KiB  
Article
Synthesis and Characterization of Thermoelectric Co2XSn (X = Zr, Hf) Heusler Alloys
by Alessandro Difalco, Francesco Aversano, Stefano Boldrini, Alberto Ferrario, Marcello Baricco and Alberto Castellero
Metals 2020, 10(5), 624; https://doi.org/10.3390/met10050624 - 11 May 2020
Cited by 7 | Viewed by 2370
Abstract
In this work, we report the results of an experimental investigation on the synthesis, structure, microstructure, mechanical, electrical conductivity, and Seebeck coefficient of Co2XSn (X = Zr, Hf) alloys. In both the alloys, the main constituent is a full Heusler-type compound [...] Read more.
In this work, we report the results of an experimental investigation on the synthesis, structure, microstructure, mechanical, electrical conductivity, and Seebeck coefficient of Co2XSn (X = Zr, Hf) alloys. In both the alloys, the main constituent is a full Heusler-type compound that coexists with small amounts of secondary phases. Both alloys show a rather high Vickers hardness (around 900 HV) and an indentation fracture toughness typical of ceramics (around 2 MPa·m1/2). The electronic transport properties of the two alloys were measured for the first time. The temperature dependence of both the Seebeck coefficient and the electrical conductivity of the two alloys shows a change in correspondence of the Curie temperature. The Seebeck coefficient reaches a constant plateau, while the electrical conductivities show a transition from metallic to semiconductor behavior. As a consequence, almost constant values of the power factor have been obtained for the power factor above the Curie temperature, which is promising for an efficient exploitation of thermal gradients of several hundreds of degree in waste heat harvesting applications. Finally, on the basis of results from this work and from the literature, the effect of the substitution of the X element on the electronic transport properties in the series Co2XSn (X = Ti, Zr, Hf) is discussed. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

13 pages, 7121 KiB  
Article
Interfacial Reactivity of the Filled Skutterudite Smy(FexNi1−x)4Sb12 in Contact with Liquid In-Based Alloys and Sn
by Giovanna Latronico, Fabrizio Valenza, Riccardo Carlini, Paolo Mele and Cristina Artini
Metals 2020, 10(3), 364; https://doi.org/10.3390/met10030364 - 11 Mar 2020
Cited by 3 | Viewed by 2323
Abstract
The study of the wettability of thermoelectric materials, as well as the search for the most proper brazing alloys, is of the maximum importance to get one step closer to the realization of a thermoelectric device. In this work, a wettability study of [...] Read more.
The study of the wettability of thermoelectric materials, as well as the search for the most proper brazing alloys, is of the maximum importance to get one step closer to the realization of a thermoelectric device. In this work, a wettability study of the filled skutterudite Smy(FexNi1−x)4Sb12 by Sn and In-based alloys is presented. Samples, having both p- and n- characters were prepared by the conventional melting-quenching-annealing technique and subsequently densified by spark plasma sintering (SPS). Afterward, wettability tests were performed by the sessile drop method at 773 K for 20 min. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analyses performed on the cross-section of the solidified drops suggest quite a complicated scenario due to the coexistence and the interaction of a large number of different elements in each analyzed system. Indeed, the indication of a strong reaction of In-based alloys with skutterudite, accompanied by the formation of the InSb intermetallic compound, is clear; on the contrary, Sn exhibits a milder reactivity, and thus, a more promising behavior, being its appreciable wettability, whilst coupled to a limited reactivity. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

15 pages, 4127 KiB  
Article
The Elusive Thomson Effect in Thermoelectric Devices. Experimental Investigation from 363 K to 213 K on Various Peltier Modules
by Valter Giaretto and Elena Campagnoli
Metals 2020, 10(2), 291; https://doi.org/10.3390/met10020291 - 23 Feb 2020
Cited by 5 | Viewed by 2926
Abstract
At steady state, in the governing equation of one-stage thermoelectric cooler, the heat resulting from Fourier conduction is balanced by heat generation due to the Joule and Thomson effects inside semiconductors. Since the heat flux observed at the junction of a semiconductor, r [...] Read more.
At steady state, in the governing equation of one-stage thermoelectric cooler, the heat resulting from Fourier conduction is balanced by heat generation due to the Joule and Thomson effects inside semiconductors. Since the heat flux observed at the junction of a semiconductor, r pair includes the Peltier effect and the Fourier heat flux caused by both the aforementioned contributions, the Thomson effect is easily masked by the Joule heat, which makes it elusive. With the aim of highlighting the contribution of the Thomson effect, measurements were carried out in the temperature range from 363 K to 213 K on different Peltier modules. The temperature dependence of the Seebeck and Thomson coefficients was evaluated as well as the electrical resistivity, and thermal conductivity of the Peltier modules examined. The results obtained show that the temperature dependence of the thermoelectric properties can reduce the cooling capacity of the Peltier module compared to what is declared in the technical datasheets of the commercial devices. The analyses allow us to conclude that an increase in the Thomson effect could have a positive effect on the performance of the Peltier only if it were possible to reduce the Joule contribution simultaneously. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

12 pages, 3497 KiB  
Article
PbO-SiO2 Based Glass Coating of PbI2 Doped PbTe
by Yatir Sadia, Idan Koron and Yaniv Gelbstein
Metals 2020, 10(2), 284; https://doi.org/10.3390/met10020284 - 21 Feb 2020
Cited by 1 | Viewed by 3038
Abstract
Thermoelectrics is one promising way of increasing the efficiency of machines and devices by reusing some of the waste heat produced. One obstacle for commercialization is the need to coat the materials to prevent sublimation and oxidation of the thermoelectric materials. Such coatings [...] Read more.
Thermoelectrics is one promising way of increasing the efficiency of machines and devices by reusing some of the waste heat produced. One obstacle for commercialization is the need to coat the materials to prevent sublimation and oxidation of the thermoelectric materials. Such coatings were designed for PbI2 doped PbTe using a (SiO2)0.68(PbO)0.3(B2O3)0.01(Na2O)0.01 based glass designed for operation at 500 °C. In this research various conditions of the coating process were examined. The effect of the atmosphere on the bonding and densification of the coating was studied using argon, vacuum and air. From the three air shows, the best bonding characteristics were from a better flow of glass and increased bonding between the oxidized PbTe layer and glass. This also created a PbO rich glass in the interface between the glass and the PbTe sample. The effect of 0, 3, and 6 wt. % NaCl additive to the solution was tested and showed that NaCl achieves better coverage due to high green body density, reaction of NaCl with the glass and removal of remaining CO2 from the glass in the form of decomposing Na2CO3. In addition, when testing the time and temperature, it was shown that the temperature of 520 °C was the minimum needed for high densification of the glass, but a duration shorter than 30 min did not allow for bonding of the glass to the substrate despite adequate densification. Finely, to obtain a well bonded coating with full coverage over the sample, the glass was coated with 6% NaCl in air at 520 °C for 30 min. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

11 pages, 2644 KiB  
Article
Features of the High-Temperature Structural Evolution of GeTe Thermoelectric Probed by Neutron and Synchrotron Powder Diffraction
by Javier Gainza, Federico Serrano-Sánchez, Norbert Marcel Nemes, José Luis Martínez, María Teresa Fernández-Díaz and José Antonio Alonso
Metals 2020, 10(1), 48; https://doi.org/10.3390/met10010048 - 25 Dec 2019
Cited by 12 | Viewed by 2994
Abstract
Among other chalcogenide thermoelectric materials, GeTe and derivative alloys are good candidates for intermediate temperature applications, as a replacement for toxic PbTe. We have prepared pure polycrystalline GeTe by using arc-melting, and investigated its structural evolution by using neutron powder diffraction (NPD) and [...] Read more.
Among other chalcogenide thermoelectric materials, GeTe and derivative alloys are good candidates for intermediate temperature applications, as a replacement for toxic PbTe. We have prepared pure polycrystalline GeTe by using arc-melting, and investigated its structural evolution by using neutron powder diffraction (NPD) and synchrotron X-ray diffraction (SXRD), as well as its correlation with the thermal variation of the Seebeck coefficient. Besides a significant Ge deficiency (~7% Ge vacancies), the thermal evolution of the unit-cell volume and Ge-Te bond lengths in the rhombohedral phase (space group R3m), below 700 K, show unexpected anomalies involving the abrupt Ge-Te bond lengthening accompanied by increased Te thermal displacements. Above 700 K, the sample is cubic (space group Fm-3m) and shows considerably larger displacement parameters for Ge than for Te, as a consequence of the random distribution of the lone pair lobes of Ge2+. The Seebeck coefficient, reaching 120 μV K−1 at 775 K, shows a shoulder in the 500–570 K region that can be correlated to the structural anomaly, modifying the electron-phonon scattering in this temperature range. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

9 pages, 4311 KiB  
Article
Thermoelectric Properties of Cu2SnSe3-Based Composites Containing Melt-Spun Cu–Te
by Degang Zhao, Lin Wang, Di Wu and Lin Bo
Metals 2019, 9(9), 971; https://doi.org/10.3390/met9090971 - 03 Sep 2019
Cited by 2 | Viewed by 2196
Abstract
In this study, the Cu–Te alloy ribbons containing nanocrystalline structures were prepared by melt spinning (MS), and were composed of Cu2−xTe, Cu2Te, Cu3−xTe, and CuTe phases. Crystal grains on both sides of the ribbons were [...] Read more.
In this study, the Cu–Te alloy ribbons containing nanocrystalline structures were prepared by melt spinning (MS), and were composed of Cu2−xTe, Cu2Te, Cu3−xTe, and CuTe phases. Crystal grains on both sides of the ribbons were uniformly distributed and the grain size of the contact surface was about 400 nm. The Cu–Te powder was incorporated into the Cu2SnSe3 powder by the ball milling process and the Cu–Te/Cu2SnSe3 thermoelectric composite was prepared by spark plasma sintering (SPS). With the amount of Cu–Te powder increasing, the carrier concentration of the Cu–Te/Cu2SnSe3 composite increased, while the carrier mobility and electrical conductivity initially increased and then decreased. Compared to the Seebeck coefficient of the Cu2SnSe3 matrix, the Seebeck coefficient of the Cu–Te/Cu2SnSe3 samples increased slightly. Moreover, the Cu–Te/Cu2SnSe3 composites had lower thermal conductivity and lattice thermal conductivity over the whole temperature range. The lattice thermal conductivity of the 0.8 vol.% Cu–Te/Cu2SnSe3 composite achieved the lowest value of 0.22 W/m·K, which was 78% lower than that of the Cu2SnSe3 matrix. The maximum figure of merit of the 0.8 vol.% Cu–Te/Cu2SnSe3 composite was 0.45 at 700 K. Full article
(This article belongs to the Special Issue Thermoelectric Compounds: Processing, Properties and Applications)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-6
Back to TopTop