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1. One cation makes a difference: structure-thermoelectric interplay in pseudo-rock salt intermetallic Eu5-xAxAl3Sb6 (A = Sr and Yb)

   https://doi.org/10.5061/dryad.mkkwh71f1  

   Garay, Luis; Borgsmiller, Leah; Zavanelli, Duncan; Snyder, G Jeffrey; Fettinger, James; Kauzlarich, Susan (January 2026, Dryad)

   Abstract: Single crystals of Eu5-xYbxAl3Sb6 and Eu5-x-ySrxYbyAl3Sb6 were synthesized by flux methods and their structures determined by single-crystal X-ray diffraction, confirming the monoclinic C2/m symmetry. The Al content in these phases can be increased from 3 to 4 by metallurgical mixing of the elements to form polycrystalline powders. A comparative study of polycrystalline synthesized Eu5Al4Sb6 and its Sr- and Yb-substituted solid solutions, along with the pseudo-quinary phase Eu2.5Sr2Yb0.5Al4Sb6, is presented. Substituting Eu2+ with the more ionic Sr2+ enhances mobility and increases the magnitude of the Seebeck coefficient, while the more covalent Yb2+ drives the system metallic, lowering Seebeck values but improving zT to 0.8 at 873 K. The quinary phase further suppresses bipolar conduction, delaying the high-temperature downturn observed in both ternary solid solutions. Across all compositions, thermal conductivities remain exceptionally low (<1 W m⁻¹ K⁻¹), enabling promising figures of merit. Methods: The datasets (Powder X-ray diffraction and Thermoelectric property measurements) for the phase pure powders are provided. Compositions are provided below. Synthesis: Phase pure powders of composition Eu_5.08Al₄Sb₄, Eu₅Al₄Sb₆, Eu_5-xA_xAl₄Sb₆ (A = Sr: x = 0.5, 2.5, 5; A = Yb: x = 0.5, 1, 1.5, 2, 5) and Eu_2.5Sr₂Yb_0.5Al₄Sb₆ Powder X-ray Diffraction (PXRD): PXRD data were collected at room temperature in air on ground single crystals and bulk powders of both solid solutions using a Bruker D8 Advance Eco diffractometer with Cu Kα radiation, 1000 W (40 kV, 25 mA), over 2θ = 15–85°, with a step size of 0.02°, and a scan rate of 1 s per step. Polycrystalline samples and ground single crystals were prepared on a zero-background holder using isopropanol. Thermal Conductivity Thermal Diffusivity (D) was measured on thin (1.19 to 1.2 mm thick) slices of Eu_5-xAxAl4Sb₆ (A = Sr and Yb) pellets using a Netzsch LFA 457 Microflash under a flow of high-purity Ar with a polished piece of Zr ribbon wrapped around the sample holder to act as an oxygen catcher. The thermal conductivity (κ) was determined using the equation: κ = D x ρ x C_p. The Dulong-Petit heat capacity value, C_p, was calculated from 3R/atom (R = gas constant).  The pellets’ density (ρ) was measured in replicate using the Archimedes method with toluene as the liquid. All samples were > 95% of their theoretical crystallographic densities, calculated using the Arrhenius method. Electrical Resistivity and Seebeck A Linseis LSR-3 instrument was used to measure resistivity and the Seebeck coefficient employing the four-probe method from 350 K to 800 K under a He atmosphere. The instrument was calibrated with a constantan standard before use. The sample geometries were bar-shaped (10.5 mm x 4 mm x 2 mm) and polished before measurements with 8 mm probes. Multiple samples were measured to ensure reproducibility, and the data were cross-checked with measurements taken at Northwestern University. At Northwestern, electrical resistivity and Hall effect data were measured using a home-built Hall instrument. This set-up uses a four-point van der Pauw resistivity measurement with molybdenum leads and a current of 100 mA. Seebeck coefficient data were collected using a home-built two-probe Seebeck instrument with chromel/Nb thermocouples. TechnicalInfo: # One cation makes a difference: structure-thermoelectric interplay in pseudo-rock salt intermetallic Eu5-*x*A*x*Al3Sb6 (A = Sr and Yb) Dataset DOI: [10.5061/dryad.mkkwh71f1](https://doi.org/10.5061/dryad.mkkwh71f1) ## Description of the data and file structure **PXRD data collection (located in folder PXRD)** PXRD data were collected at room temperature in air on ground single crystals and bulk powders of both solid solutions using a Bruker D8 Advance Eco diffractometer with Cu Kα radiation, 1000 W (40 kV, 25 mA), over 2θ = 15–85°, with a step size of 0.02°, and a scan rate of 1 s per step. Polycrystalline samples were prepared on a zero-background holder using isopropanol. **Thermal Conductivity (located in folder TE properties)** Thermal Diffusivity (*D)* was measured on thin (1.19 to 1.2 mm thick) slices of Eu5-*x*A*x*Al4Sb6 (A = Sr and Yb) pellets using a Netzsch LFA 457 Microflash under a flow of high-purity Ar with a polished piece of Zr ribbon wrapped around the sample holder to act as an oxygen catcher. The thermal conductivity (κ) was determined using the equation: κ = *D* x ρ x C~p~. The Dulong-Petit heat capacity value, C~p~, was calculated from 3*R*/atom (R = gas constant).  The pellets’ density (ρ) was measured in replicate using the Archimedes method with toluene as the liquid. All samples were > 95% of their theoretical crystallographic densities, calculated using the Arrhenius method. **Electrical Resistivity, Seebeck, and Hall Data Collection** A Linseis LSR-3 instrument was used to measure resistivity and the Seebeck coefficient employing the four-probe method from 350 K to 800 K under a He atmosphere. The instrument was calibrated with a constantan standard before use. The sample geometries were bar-shaped (10.5 mm x 4 mm x 2 mm) and polished before measurements with 8 mm probes. Multiple samples were measured to ensure reproducibility, and the data were cross-checked with measurements taken at Northwestern University. At Northwestern, electrical resistivity and Hall effect data were measured using a home-built Hall instrument. This set-up uses a four-point van der Pauw resistivity measurement with molybdenum leads and a current of 100 mA. Seebeck coefficient data were collected using a home-built two-probe Seebeck instrument with chromel/Nb thermocouples. ### Files and variables #### File: EuSrYbAlSb6_ChemMater_D.zip **Description:** There are 2 folders for each type of data: Powder X-ray Diffraction (**PXRD**) data for the polycrystalline synthesized samples indicated above; (**TE Properties**) Thermoelectric properties provides the electrical resistivity and Seebeck coefficient as a function of temperature for the polycrystalline samples. #### PXRD folder has 3 sub-folders: EuYbSr, Sr, Yb. The sub-folders contain dataset (.cvs) indicated by the cation composition of the polycrystalline synthesized sample. **Sub-Folder** **EuYbSr**: contains the PXRD data for Eu~2.5~Sr~2~Yb~0.5~Al~4~Sb~6~ **Sub-Folder** **Sr**: contains the PXRD data for Eu~2.5~Sr~2.5~Al~4~Sb~6~; Eu~4.5~Sr~0.5~Al~4~Sb~6~; Sr~5~Al~4~Sb~6~ **Sub-Folder** **Yb**: contains the PXRD data for Yb~5~Al~4~Sb~6;~ Eu~4~Yb~1~Al~4~Sb~6~; Eu~3~Yb~2~Al~4~Sb~6~; Eu~3.5~Yb~1.5~Al~4~Sb~6~; Eu~4.5~Yb~0.5~Al~4~Sb~6~ Each *.cvs dataset is indicated by the sample composition. Each dataset contains a header with the composition; column 1: 2-theta (degree); column 2: intensity (arbitrary units (a.u.)). #### **TE** **Properties** folder has 4 sub-folders: **Eu,** **EuYbSr**, **Sr**, **Yb**. The sub-folders contain dataset (*.cvs) indicated by the cation composition of the polycrystalline synthesized sample. Each *.cvs file has the composition of the element in the A column, and Temperature/K and Resistivity/ mOhm•cm; Seebeck Coefficient/ µV/K; Thermal Conductivity/W •m^-1^ •K^-1^ and ( if collected) carrier concentration/ h/cm^3^ and Hall mobility /cm^2^•V^-1^•s^-1^ **Sub-Folder Eu**: contains TE data for Eu~5~Al~4~Sb~6~; Eu~5.08~Al~4~Sb~6~; **Sub-Folder EuYbSr:** contains TE data for Eu~2.5~Sr~2.0~Yb~0.5~Al~4~Sb~6~ **Sub-Folder Sr:** contains TE data for Sr~5~Al~4~Sb~6~; Eu~2.5~Sr~2.5~Al~4~Sb~6~; Eu~4.5~Sr~0.5~Al~4~Sb~6~; **Sub-Folder Yb:** contains TE data for Yb~5~Al~4~Sb~6;~ Eu~4~Yb~1~Al~4~Sb~6~; Eu~3~Yb~2~Al~4~Sb~6~; Eu~3.5~Yb~1.5~Al~4~Sb~6~; Eu~4.5~Yb~0.5~Al~4~Sb~6~; #### 

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2. Data from: Advancing the Ca14AlSb11 structure type: Synthesis and characterization of Yb14CdSb11 for thermoelectric applications

   https://doi.org/10.5061/dryad.9w0vt4brw  

   Kauzlarich, Susan; Opara, Ivan (January 2025, Dryad)

   Abstract: The ternary phase Yb14CdSb11 has been synthesized using both flux and polycrystalline methods. The crystal structure was determined via single-crystal X-ray diffraction, revealing that it crystallizes in the Ca14AlSb11 structure type (I41/acd space group with unit cell parameters of a = 16.5962(2) Å and c = 22.1346(5) Å, 90 K, Z = 8, R1 = 2.65 %: wR2 = 4.58 %. The polycrystalline form of the compound was synthesized from a stoichiometric reaction of Yb4Sb3, CdSb, Yb, and Sb. The elemental composition was confirmed using scanning electron microscopy and energy-dispersive spectroscopy (SEM-EDS), and phase purity was verified by powder X-ray diffraction (PXRD). Thermoelectric measurements, including resistivity, Seebeck coefficient, thermal conductivity, Hall carrier concentration, and Hall mobility, were conducted from 300 to 1273 K. Yb14CdSb11 exhibited a peak zT = 0.80 at 1150 K. Carrier concentration and Hall mobility ranged from to  holescm^-3^ and from 1019 cm²V-¹s-^¹, respectively. This carrier concentration is lower than that reported for the Zn or Mn analogs, leading to a lower thermoelectric figure of merit at high temperatures. However, with appropriate doping, it is expected that this phase should also be a promising p-type candidate for high-temperature energy conversion applications. TechnicalInfo: # Data from: Advancing the Ca14AlSb11 structure type: Synthesis and characterization of Yb14CdSb11 for thermoelectric applications ## Description of the data and file structure ### Files and variables #### File: Dryad_PXRD_data.zip **Description:**  Heat capacity, powder x-ray diffraction data for CdSb, Yb4Sb3, and Yb14CdSb11, carrier concentration, mobility, electrical resistivity, Seebeck coefficients, thermal conductivity, and zT for Yb14CdSb11. The zip file entitled Yb14CdSb11_All_Data.zip includes data files with Heat Capacity ("Heat capacity_YbCdSb.dat"), Powder X-ray Diffraction data of the binary precursors ("PXRD CdSb.txt", "PXRD Yb4Sb3.txt", and "PXRD_Yb14CdSb11.txt", and Thermoelectric transport data. **Heat Capacity** Heat capacity measurements of a single crystal were done in a Quantum Design PPMS from 2 K to 300 K. **Powder X-ray Diffraction (PXRD)** PXRD data were collected on each sample using a Bruker zero background holder on a Bruker D8 Eco Advanced employing Cu K∝ radiation (λ = 1.54 Å) with a Ni filter to remove Cu Kβ. **Seebeck Coefficient and Electrical Resistivity** Seebeck, resistivity, and Hall data were collected as a function of temperature under high vacuum at the Jet Propulsion Laboratory (JPL). Resistivity and Hall Van der Pauw measurements were performed with a current of 100 mA and a 0.8 T magnet. Seebeck coefficient was measured using a custom two-probe instrument under a high vacuum. Temperature-dependent Seebeck coefficients, electrical resistivity, and thermal conductivity were fit to six-order polynomials to calculate* zT* values. T (K):** **Temperature in Kelvin; r-fit (mΩ·cm): electrical resistivity; S-fit (µV/K): Seebeck coefficient; L- Lorenz number; K-fit: total thermal conductivity; K_e: electronic thermal conductivity; K_L: lattice (phonon) thermal conductivity; PF: power factor; ZT (dimensionless): thermoelectric figure of merit. **Thermal Conductivity** Thermal diffusivity was measured on densified pellets using laser flash analysis on a Netzsch LFA 475 Microflash under Ar(g) flow. The fully densified pellet was sliced into a thin disk (<1.5 mm) and polished until flat with parallel sides. The density of this disk was measured using Archimedes' method with toluene as the liquid. The heat capacity of Yb14CdSb11 was estimated using an adjusted heat capacity, Cp, based on the experimental heat capacity for Yb14MnSb11 and adjusting for the molecular weight of the Yb14CdSb11 analog: Where MM is the molar mass of the respective compounds. This adjusted heat capacity was employed to give the total thermal conductivity according to the equation: κ = D × Cp × *d* (D = measured diffusivity; Cp = heat capacity adjusted; *d* = the temperature-adjusted density).  The coefficient of thermal expansion (CTE) measured for Yb14MnSb11 was also employed. This procedure is consistent with past practice for compounds with the Yb14MSb11, compared to previously published work. 

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3. Utilizing magnetization and spin in thermoelectric applications

   https://doi.org/10.1557/s43577-025-00941-8  

   Watzman, Sarah J; Kikkawa, Takashi; Skinner, Brian; Uchida, Ken-ichi (August 2025, MRS Bulletin)

   Abstract The combined use of heat, charge, and spin transport gives rise to new or deeply altered thermoelectric properties from those found in conventional, nonmagnetic thermoelectric transport; these phenomena include the magneto-Seebeck, Nernst, magnon drag, and spin Seebeck effects. Here, we explore both electron-driven and magnon-driven magneto-thermoelectric effects stemming from different origins depending on if the effect is longitudinal, where the electric field and thermal gradient are collinear, or transverse, where the electric field and thermal gradient are orthogonal. We consider both a Lorentz force acting on charge carriers in nonmagnetic conductors and the spin–orbit interaction acting on spin-polarized electrons in magnetic materials. Both intrinsic and extrinsic sources of skew forces on electrons or anomalous velocities offer promising avenues for generating new functionalities and applications in the burgeoning field of magneto-thermoelectrics and transverse thermoelectrics. Adding magnetism as a design degree of freedom offers more candidate classes of materials, such as topological, metallic, and amorphous materials, for consideration in the field of thermoelectrics. Graphical abstract 

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4. Optimization of the composition Eu5+xAl3+ySb6 and thermoelectric figure of merit

   https://doi.org/10.5061/dryad.1zcrjdg3q  

   Garay, Luis; Borgsmiller, Leah; Snyder, Jeffrey; Kauzlarich, Susan (January 2025, Dryad)

   Abstract: Eu5.08Al3Sb6 can be described as a pseudo rock salt-like “(Eu/Al4)Sb” structure. The polycrystalline synthesis of Eu5+xAl3+ySb6 was optimized. The compositions exhibit n-type transport behavior, ultra-low thermal conductivity, and a high Seebeck coefficient. The Eu5.08Al4Sb6 shows a promising zT of 0.8 at a temperature of 873 K. TechnicalInfo: # Optimization of the composition Eu5+xAl3+ySb6 and thermoelectric figure of merit [https://doi.org/10.5061/dryad.1zcrjdg3q](https://doi.org/10.5061/dryad.1zcrjdg3q) ## Description of the data and file structure The data sets are: (1) powder x-ray diffraction (PXRD): PXRD_ChemComm.zip, thermal gravimetric (TG)- Differential scanning calorimetry (DSC): TGDSC_ChemComm.zip and transport data: TransportData_ChemComm.zip **Powder X-ray Diffraction (PXRD):** PXRD_ChemComm.zip PXRD data were collected with a Bruker D8 Advance Eco Diffractometer using Cu Kα radiation from 2θ = 20° —80°  with a step size of 0.02 ˚ and scan rate of 1 s/step at room temperature in air. The polycrystalline samples were ground inside an Ar-filled glove box and plated on a zero-background holder with isopropanol. **Thermogravimetric (TG)/Differential Scanning Calorimetry (DSC):** TGDSC_ChemComm.zip Melting point studies of aluminum excess were done on polished pellet pieces of Eu5+*x*Al3+*y*Sb6 using TG/DSC (STA 449 F3 Jupiter, Netzsch) from room temperature up to 800°C with a heating rate of 10K/min under a 50 mL/min flow of Ar.  A piece of Aluminum metal (Aluminum shot, approx. 4-8mm (0.2-0.3in), Puratronic™, 99.999% (metals basis)) was used as a reference. **Thermal Conductivity:** TransportData_ChemComm.zip Thermal Diffusivity (*D) was measured on thin (1.19 to 1.2 mm thick) slices of Eu5+*x*Al3+*y*Sb6 pellets using a Netzsch LFA 457 Microflash under a flow of high purity Ar with a polished piece of Zr ribbon wrapped around the sample holder to act as an oxygen catcher. The thermal conductivity (κ) was determined from the equation: κ = *D* x ρ X Cp. All the pellets’ density (ρ) was measured multiple times using the Archimedes method using toluene as the liquid. All samples were > 95% of their theoretical crystallographic densities, calculated using the Arrhenius method. **Transport Measurements:** TransportData_ChemComm.zip  A Linseis LSR-3 instrument was used to measure resistivity and Seebeck coefficient employing the four-probe method from 350K to 800K under He atmosphere. The sample geometries were bar-shaped ( 10.5mm x 4mm x 2mm) using 8 mm probes and polished before measurements. Multiple samples were measured to ensure reproducibility, and the data was cross-checked using measurements at JPL and Northwestern. The Seebeck coefficient was measured using a light pulse technique as described above using W/Nb thermocouples. Electrical resistivity (ρ) was measured using the van der Pauw (VDP) technique with a current of 10 mA. Electrical resistivity and Hall effect data were measured using a home-built Hall effect instrument for the samples measured at Northwestern.1 This set-up utilizes a four-point Van der Pauw resistivity measurement with molybdenum leads and a current of 100 mA. Seebeck coefficient data was collected using a home-built two-probe Seebeck instrument with chromel/Nb thermocouples. ### Files and variables #### File: PXRD_ChemComm.zip **Description:** Powder X-ray diffraction data files, collected according to the description provided above. **Variables:** x, y where x = two-theta (˚) and y = X-ray diffraction Intensity (arbitrary units) **Files:** Eu5_08Al3_3Sb6.xy = sample composition Eu5.08Al3.3Sb6 Eu5_08Al4Sb6.xy = sample composition Eu4.08Al4Sb6 Eu5Al3_3Sb6.xy = sample composiiton Eu5Al3.3Sb6 Eu5Al3Sb6.xy = sample composition, Eu5Al3Sb6 Eu5Al4Sb6.xy = sample composition Eu5Al4Sb6 #### File: TGDSC_ChemComm.zip **Description:** Thermogravimetric and differential scanning calorimetry data collected according to the description provided above. **Variables:** Temperature/˚C; Time/min; DSC/(mW/mg); Mass/%; Gas Flow (purge2)/(ml/min); Gas Flow(protective)/(ml/min); Sensit./(uV/mW) **Files:** ExpDat_Aluminum_shot_800C_1.csv = (segment 1) experimental data for aluminum shot taken from 20 ˚C to 800 ˚C. ExpDat_Aluminum_shot_800C_2.csv = (segment 2) experimental data for aluminum shot taken from 800 ˚C to 20˚C. ExpDat_Eu5_08Al3_3Sb6_800C_1.csv = (segment 1) experimental data for sample composition Eu5.08Al3.3Sb6 taken from 20 ˚C to 800 ˚C. ExpDat_Eu5_08Al3_3Sb6_800C_2.csv = (segment 2) experimental data for sample composition Eu5.08Al3.3Sb6 taken from 800 ˚C to 20˚C. ExpDat_Eu5_08Al4Sb6_800C_1.csv = (segment 1) experimental data for sample composition Eu5.08Al4Sb6 taken from 20 ˚C to 800 ˚C. ExpDat_Eu5_08Al4Sb6_800C-2.csv = (segment 2) experimental data for sample composition Eu5.08Al4Sb6 taken from 800 ˚C to 20˚C. ExpDat_Eu5Al3_3Sb6_800C_1.csv = (segment 1) experimental data for sample composition Eu5Al3.3Sb6 taken from 20 ˚C to 800 ˚C. ExpDat_Eu5Al3_3Sb6_800C_2.csv = (segment 2) experimental data for sample composition Eu5Al3.3Sb6 taken from 800 ˚C to 20 ˚C. ExpDat_Eu5Al4Sb6_800C_1.csv = (segment 1) experimental data for sample composition Eu5Al4Sb6 taken from 20 ˚C to 800 ˚C. ExpDat_Eu5Al4Sb6_800C_2.csv = (segment 2) experimental data for sample composition Eu5Al4Sb6 taken from 800 ˚C to 20 ˚C. #### File: TransportData_ChemComm.zip **Description:** Hall data and Seebeck data files containing Temperature dependent Hall resistivity, mobility, resistivity, Seebeck. *Variables for Hall Data:* Sample thickness in mm; Temperature/(˚C) ; Temperature/(K); Resistivity/(mohm.cm); Conductivity/(S/cm); Carrier Concentration/(/cm3); Hall Mobility/ (cm2/Vs); Hall Resistivity = R_H/(cm3/C); temperature for resistance = T_Res/(˚C); temperature for Hall data collection = T_Hall/(˚C); Resistance Standard deviation = Res*_*Std/(%); Hall resistance standard deviation = RH*_*Std/(%); Hall mobility standard deviation = muH Std/(%); Applied magnetic field = B field/(Gauss); applied current for resistivity = I_Res/(mA); van der Pauw ration = vdP ratio; resistivity time = Res. Time= time and date for the measurement; Hall time = Hall. Time = time and date for the Hall measurement; lead resistance for the 4 leads = Lead Res. 1, Lead Res. 2, Lead Res. 3, and Lead Res. 4 in Ohm; Probe to ground resistance = Probe-GND REsistance/(Ohm); thermocouple 1 = TC1/(˚C) was not used; thermocouple 2 = TC2/(˚C) was not used. **Variables for Seebeck Data**: Temperature = T/(˚C); Seebeck coefficient = seebfit/(uV/K) **Files:** Eu5_08Al3_3Sb6_HallData.csv = Hall data for sample composition Eu5.08Al3.3Sb6 taken from 20 ˚C to 550 ˚C. Eu5_08Al4Sb6_HallData.csv = Hall data for sample composition Eu5.08Al4Sb6 taken from 20˚C to 550 ˚C. Eu5Al3_3Sb6_HallData.csv = Hall data for sample composition Eu5Al3.3Sb6 taken from 20˚C to 550 ˚C. Eu5Al4Sb6_HallData.csv= Hall data for sample composition Eu5Al4Sb6 taken from 20˚C to 550˚C. Eu5_08Al3_3Sb6_Seebeck.csv = Seebeck data for sample composition Eu5.08Al3.3Sb6 taken from 50 ˚C to 600 ˚C. Eu5_08Al4Sb6_Seebeck.csv = Seebeck data for sample composition Eu5.08Al5Sb6 taken from 50 ˚C to 600 ˚C. Eu5Al3_3Sb6_Seebeck.csv = Seebeck data for sample composition Eu5Al3.3Sb6 taken from 50˚C to 600 ˚C. Eu5Al4Sb6_Seebeck.csv = Seebeck data for sample composition Eu5Al4Sb6 taken from 50˚C to 600 ˚C. **ThermalConductivity Folder:** thermal diffusivity data of all samples; conversion to thermal conductivity data provided in LJGEu5Al3Sb6*_*TD_TC.xlsx file. **Variables:** Sample thickness = #Thickness_RT/(mm); sample diameter = #Diameter/(mm); argon gas flow = #Gas flow/(ml/min); shot number; data collection time = #Time/(min); temperature = #Temperature/(˚C); diffusivity data = #Diffusivity/(mm^2/s); standard deviation based on 3 shots = #Std_Dev/(mm^2/s) Files:  Eu5_08Al3_3Sb6TD.csv = thermal diffusivity data for sample composition Eu5.08Al3.3Sb6 taken from 10 ˚C to 550 ˚C. Eu5_08Al4Sb6_TD.csv = thermal diffusivity data for sample composition Eu5.08Al4Sb6 taken from 10 ˚C to 550 ˚C. Eu5Al3_3Sb6_TD.csv = thermal diffusivity data for sample composition Eu5.08Al3.3Sb6 taken from 10 ˚C to 550 ˚C. Eu5Al4Sb6_TD.csv = thermal diffusivity data for sample composition Eu5Al4Sb6 taken from 10 ˚C to 550 ˚C. LJGEu5Al3Sb6_TD_TC.xlsx = Data file providing the conversion of all compositions from thermal diffusivity data to thermal conductivity values. All compositions indicated with headers with temperature = T/(˚C); temperature = T/(K); diffusivity (mm2/s); density /(gm/cm3); Heat Capacity/ ; Thermal Conductivity/(W/mK); Thermal Conductivity/(mW/cmK); 

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5. Characterization and Performance of Cement-based Thermoelectric Materials

   Jani, R.; Holmes, N.; West, R.; Gaughan, K.; Liu, X.; Orisakwe, E.; Johnston, C.; Qu, M.; Kohanoff, J.; Stella, L.; et al (August 2020, Civil Engineering Research in Ireland (CERI) 2020)

   Thermoelectric materials enable the direct conversion of thermal energy to electricity. Ambient heat energy harvesting could be an effective route to convert buildings from being energy consumers to energy harvesters, thus making them more sustainable. There exists a relatively stable temperature gradient (storing energy) between the internal and external walls of buildings which can be utilized to generate meaningful energy (that is, electricity) using the thermoelectric principle. This could ultimately help reduce the surface temperatures and energy consumption of buildings, especially in urban areas. In this paper, ongoing work on developing and characterizing a cement-based thermoelectric material is presented. Samples are fabricated using cement as a base material and different metal oxides (Bi₂O₃ and Fe₂O₃) are added to enhance their thermoelectric properties. A series of characterization tests are undertaken on the prepared samples to determine their Seebeck coefficient, electrical and thermal conductivity. The study shows that cement paste with additives possesses physical properties in the range of semiconductors whereby, initially, the resistivity values are low but with time, they increase gradually, thus resulting in lower electrical conductivity. The thermal conductivity of the cement paste with additives is lower than the control sample. Seebeck coefficient values were found to be relatively unstable during the initial set of measurements because the internal and external environment needed to be kept in a thermally stable condition to achieve steady results. The detailed analysis helped determine and eliminate the source of errors in the characterization process and obtain repeatable results. Parameters such as moisture content, temperature, and age were found to have a significant impact on the properties of cement-based thermoelectric materials. 

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