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Article

Effects of Ti and Sn Substitutions on Magnetic and Transport Properties of the TiFe2Sn Full Heusler Compound

by
Bogdan Popescu
,
Ilhame Assahsahi
,
Magdalena Galatanu
and
Andrei Galatanu
*
National Institute of Materials Physics, Atomistilor 405 A, 077125 Magurele, Ilfov, Romania
*
Author to whom correspondence should be addressed.
Inorganics 2024, 12(12), 322; https://doi.org/10.3390/inorganics12120322
Submission received: 4 November 2024 / Revised: 2 December 2024 / Accepted: 7 December 2024 / Published: 11 December 2024
(This article belongs to the Special Issue New Semiconductor Materials for Energy Conversion)
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Versions Notes

Abstract

:
The synthesis of polycrystalline TiFe2Sn samples by a route including arc melting and spark plasma sintering with Hf, Y, and In substitutions at the Ti and Sn sites is investigated. For a reduced amount of substitution, around 2 at%, the samples are single phase, while for increased amounts, secondary phases segregate. As is characteristic of these compounds, the Fe-Ti atomic disorder generates a weak ferromagnetic ordering, which is also influenced by the type of substitutional atoms and the secondary phases in the samples with a higher Hf content. The Seebeck coefficient values show an increase for Ti0.98Hf0.02Fe2Sn and for samples with an adjusted Sn content, resulting in slightly increased power factor values. These values reach a maximum for Ti0.98Hf0.02Fe2Sn at approximately 300 K and for TiFe2Sn1.05 at approximately 325 K, namely, 2.69 × 10⁻4 Wm−1K−2 and 2.52 × 10⁻4 Wm−1K−2, respectively. The thermal conductivity of all the samples with substitutions increases with respect to the pristine sample. The highest figure of merit value of 0.016 is also obtained for Ti0.98Hf0.02Fe2Sn at 325 K.

1. Introduction

The discovery of Heusler alloys more than a century ago opened up the possibility of designing a countless number of compounds with a wide variety of properties, including spintronics [1,2], optoelectronics [3], spin gapless semiconductors [4,5], ferromagnetism [2,6], thermoelectricity [7,8], superconductors [9,10], topological insulators [11,12], and shape memory alloys [1,13,14]. Since Heusler alloys are non-toxic, environmentally friendly materials with easily tunable band gaps, they have stimulated the research in the field of thermoelectricity. Although the thermoelectric (TE) properties of half-Heusler (HH) alloys [15] are far beyond those of full-Heusler (FH) alloys, the latter have attracted increasing attention after the observation of a large Seebeck coefficient (|S| > 150 μV K−1) in VFe2Al [16,17]. This encouraged a further search for new FH alloys with potentially better TE properties and led to investigations on TiFe2Sn, which has been noted for its lower thermal conductivity [18].
TiFe2Sn, an FH compound with high thermal and chemical stability, is composed of elements that are abundant in the Earth’s crust and has been theoretically predicted to have enhanced thermoelectric properties under appropriate doping. For example, these studies suggest that n-type doping at the Ti site could improve the power factor by increasing the number of valence electrons for TiFe2Sn from 24 to 24.06 [19]. However, experimental investigations show that these theoretical assumptions are not confirmed due to the challenges associated with obtaining samples without defects, impurity phases, or compositional inhomogeneities. In particular, the partial substitution of Ti by V atoms in Ti1−xVxFe2Sn [20] leads to a change in the conductivity from p-type to n-type and yields low Seebeck coefficient values of about 35 μVK−1 at room temperature (RT), which is significantly lower than the predicted values (−300 μVK−1 at 300 K [19]). Similarly, the substitution of Ti with isoelectronic Zr atoms [21] is unsuccessful, decreasing S by ~30% over the temperature range measured. Attempts to dope the Fe site with n-type Co [22] or p-type Mn or Re [23,24] have been rather ineffective, producing only a marginal improvement in the thermoelectric properties at low doping levels. In addition, the thermoelectric transport of Sb-doped Fe2TiSn above RT is strongly influenced by the sample preparation protocol, where a low annealing temperature of 973 K or 1123 K [25,26] for 7–8 days yields results contrary to those predicted by theory. However, a higher annealing temperature of ~1173 K and longer duration of ~13 days [27] leads to grain growth and improved phase homogeneity, resulting in samples with a larger S of ~56 μV/K at RT (in TiFe2Sn0.8Sb0.2).
Despite the fact that the figure of merit values have been predicted to reach unity for TiFe2Sn [28], the experimental values are lagging behind, reaching only approximately 0.015 [18,21,23]. This is at least two orders of magnitude lower than that of traditional TE materials, such as bismuth tellurides [29], skutterudites [30,31], or magnesium silicide stannide [32,33,34]. Given the challenges in achieving the theoretically predicted thermoelectric performance in TiFe2Sn, exploring alternative substitutions at both the Ti and Sn sites with p-type or isoelectronic elements offers a promising way to improve thermoelectric performance. Substituting the Ti site with elements such as Y or Hf, or the Sn site with In, may have beneficial effects such as modifying the carrier concentration, reducing the anti-site disorder, or tuning the electronic structure, which could lead to improvements in both electrical conductivity and the Seebeck coefficient. This study aims to systematically investigate the effects of these substitutions on the thermoelectric properties of TiFe2Sn, focusing on how p-type or isoelectronic doping can address the limitations of current doping strategies and potentially unlock higher power factors and improved thermoelectric efficiency in full-Heusler alloys.

2. Results

2.1. Structure and Morphology

The room temperature XRD patterns of all samples can be indexed to the cubic Fm-3m, No. 225 (L21) structure. Rietveld analysis performed on the XRD data shows that the lattice parameter varies with the successful substitution of different types of atoms (see Table 1). Figure 1a shows an example of the Rietveld analysis for the pristine sample compared to the samples with substitutions. Except for Hf0.25Ti0.75Fe2Sn, all samples are single phase. At higher Hf contents, a rhombohedral (P 63/mmc) secondary phase of the HfFe2 type segregates, accounting for about 17 v% of the sample, together with a small amount of unreacted Hf (see also the Supplementary Materials).
The SEM investigations show that the TiFe2Sn samples are well compacted after SPS (Figure 1). Images of fractured specimens show that the samples are composed of relatively large agglomerations of grains (Figure 1b). Defects are visible on the surface of the samples, primarily occurring during polishing when substantial fragments are dislodged due to the mechanical fragility of the material. However, samples with high substitution levels, such as Hf0.25Ti0.75Fe2Sn, show phase segregation, as indicated by the regions of different morphology on the SEM images (lighter regions on the right in Figure 1b). EDX investigations show that the composition in these regions is close to HfFe2, while the matrix composition is approximately Ti1.018Hf0.122Fe1.813Sn1.046. Other sample compositions checked by EDX are close to the calculated compositions. For example, the average composition of the pristine sample is Ti1.069Fe1.952Sn0.979, while the sample with a small Hf substitution is Ti1.003Hf0.054Fe1.965Sn0.978.

2.2. Magnetism

Due to anti-site disorder and fluctuations in the Fe:Ti ratio, TiFe2Sn compounds, which are nominally non-magnetic, exhibit weak ferromagnetism [35]. Magnetic correlations arise when Fe and Ti atoms interchange positions; consequently, the magnetic strength in this system is directly related to the disorder of Fe sites. The samples with a lower level of substitution show that magnetic susceptibility χ(T) increases below 250 K, indicating weak ferromagnetic ordering (see Figure 2a). In contrast, Hf0.25Ti0.75Fe2Sn, influenced by additional secondary phases, undergoes a ferromagnetic transition at a higher temperature (~350 K), with magnetic susceptibility values by an order of magnitude greater than those of TiFe2Sn. Above 200 K, χ(T) exhibits a Curie-type behavior (χ(T) = C/T), but diverges from this trend below this temperature, adopting a Curie–Weiss behavior: χ(T) = C/(T − θ) + χ0 (C = NAμeff2/(3 kB)), where NA is Avogadro’s number, μeff is the effective moment, kB is the Boltzmann constant, and θ is the Curie–Weiss temperature. The μeff values listed in Table 2 indicate that the magnetism in these samples is influenced not only by the Fe atoms (with μeff ~5.92 μB) but also by additional factors. For instance, in Ti0.75Hf0.25Fe2Sn, the higher μeff may result from the interaction between the magnetism of the primary Heusler phase and that of the HfFe2 phase, which has μeff~3.12 μB [36].
The magnetization response to magnetic field variations for all compositions (as shown in Figure 2b) indicates that, with the exception of Ti0.758Hf0.25Fe2Sn, saturation magnetization is not achieved even at an applied field of 7 T. Furthermore, the magnetization of the samples demonstrates no hysteresis upon field reversal (as seen in the inset of Figure 2b), implying a lack of long-range ferromagnetic order within the system, even at the lowest measurement temperature of 2 K. The M(H) curves conform well to the saturation approach law M(H) = MS [1 − (a/H) − (b/H2)] + χH, where MS denotes saturation magnetization, while a, b, and χ are constants. As indicated in Table 2, all substitutions yield a slight increase in saturation magnetization, with the highest value recorded for Ti0.75Hf0.25Fe2Sn, which is nearly an order of magnitude greater than that of TiFe2Sn.

2.3. Transport Properties

Figure 3a,b show the temperature dependence of the electrical conductivity (σ), Seebeck coefficient (S) and power factor (PF) for the samples with substitutions at the Ti site and Sn site, respectively. All the samples show metallic-like behavior at lower temperature, with σ decreasing with increasing temperature, and semiconducting behavior above a temperature specific to each sample. None of the substitutions of Sn or of Ti with small amounts of In or Y significantly change the σ values. On the other hand, both HfxTi1−xFe2Sn samples show significantly increased conductivity values over the whole temperature range of measurement. The Seebeck coefficient of all samples is positive with a maximum value around RT, indicating p-type conduction over the entire temperature range studied. In most cases, the substitutions made lead to lower values of S, such as for In, Y, or Hf (x = 0.25). In particular, higher values of S are observed for the samples with more Sn as well as for the one with Hf (x = 0.02). Under these conditions, the power factor, PF = S2σ, has peak values for Hf0.02Ti0.98Fe2Sn and TiFe2Sn1.05 of 2.69 × 10−4 Wm−1K−2 @ 300 K and 2.52 × 10−4 Wm−1K−2 @ 325 K, respectively, which is an increase of about 32% and 24%, respectively, compared to the pristine sample (~2.03 × 10−4 Wm−1K−2 @ 325 K).
As shown in Figure 4, the total thermal conductivity, κ, is rather high for a thermoelectric material, ranging from 4 to 10 Wm−1K−1 for TiFe2Sn in the interval from RT to 900 K. For all the other samples, κ increases over the entire measurement range, with the highest values observed for Hf0.25Ti0.75Fe2Sn. For a better understanding, the electronic part of thermal conductivity, κe, is calculated according to the Wiedemann–Franz law [37], κe = LTσ, where L is the Lorenz number (2.44 × 10−8 V2K−2). The lattice thermal conductivity is calculated using κL = κ − κe. As can be seen in Figure 4, the major contribution to the thermal conductivity below 400 K is given by the lattice term, κL. At temperatures above 500 K, the electronic part, κe, becomes the dominant factor due to the increased thermal activation of the carriers.
The temperature dependence of the figure of merit, ZT = S2Tσ/κ, shown in Figure 5, exhibits a similar trend to that observed for PF and S (see Figure 3). Its maximum values are recorded slightly above RT in all cases, with the exception of Hf0.02Ti0.98Fe2Sn, which surpasses TiFe2Sn to reach a maximum of 0.016 ± 0.002 at 325 K. This value represents a 6.6% improvement over the maximum calculated for the bare sample, which is 0.015 ± 0.002 at 325 K. Other studies report comparable values for TiFe2Sn alloys, such as ~0.013 at 300 K [21] or ~0.022 at 375 K in TiFe1.9815Mn0.0185Sn [23].

3. Discussion

The properties of TiFe2Sn are very sensitive to anti-site disorder and non-stoichiometry, especially with regard to the Fe:Ti ratio [38,39]. Our structural and compositional investigations suggest a certain degree of disorder between the Fe and Ti positions, as indicated by the analysis of the reflections corresponding to the (111), (200), and (220) crystal planes [24], and that the Fe:Ti ratio is different from 2:1. These facts affect the material properties; the first evidence of this is the appearance of the weak ferromagnetic behavior in otherwise non-magnetic materials, according to the Slater–Pauling rule [40]. The substitutions change the Fe:Ti ratio and thus the magnetism of the samples. At low temperatures, the magnetic susceptibility χ(T) of TiFe2Sn compounds shows distinct variations depending on the specific doping elements. Hf-doped compounds, especially Hf0.25Ti0.75Fe2Sn, show a pronounced increase in χ with decreasing temperature, suggesting the onset of strong ferromagnetic correlations, possibly indicating Curie–Weiss behavior. In contrast, compounds such as TiFe2Sn and TiFe2Sn0.98In0.02 show a moderate increase, indicating weaker magnetic interactions. Yttrium substitution (Y0.02Ti0.98Fe2Sn) significantly suppresses the low-temperature susceptibility, indicating reduced magnetic interactions in this case. Notably, doping with Hf and Y produces opposite effects on magnetic behavior, enhancing and suppressing the magnetic correlations, respectively.
Substitutions not only introduce additional structural defects but also enhance the anti-site disorder and Fe:Ti non-stoichiometry effects. Therefore, they can alter the band structure and consequently the electrical transport of TiFe2Sn systems [26]. In Hf-doped samples, in particular Hf0.25Ti0.75Fe2Sn, the conductivity is significantly higher due not only to the increased carrier concentration, probably due to the substitution of Hf for Ti or Fe, but also to the contributions of the secondary phases (metallic Hf and HfFe2). In contrast, Y-doped samples exhibit lower conductivity, suggesting that although Y should increase the hole concentration, it increases structural disorder, which scatters charge carriers and decreases their mobility. Sn-rich samples (TiFe2Sn1.05) show slightly higher conductivity, possibly due to reduced non-stoichiometry effects and anti-site disorder, while In-doped samples show lower conductivity, probably due to increased scattering caused by lattice defects induced by indium atoms, similar to the Y case.
The Seebeck coefficient values of Hf0.25Ti0.75Fe2Sn are the lowest, reflecting the inverse relationship between carrier concentration and thermopower. Y doping results in slightly lower S compared to TiFe2Sn, due to a slightly higher carrier concentration. In the Sn-rich sample, the excess of Sn introduces more electrons, reducing the overall hole concentration, and possibly reducing the structural disorder, resulting in a higher Seebeck coefficient. Indium doping could increase the hole concentration but could also introduce more scattering centers, further lowering S.
The thermal conductivity of TiFe₂Sn-based compounds increases consistently with temperature for all compositions. This increase is largely attributed to the electronic thermal conductivity, κₑ, which is directly related to the carrier behavior discussed in the previous sections. As the temperature increases, the number of thermally excited carriers increases, thereby increasing κₑ. The lattice thermal conductivity (κₗ), which is governed by phonon transport, has a more complex temperature dependence. In undoped TiFe₂Sn, κₗ remains relatively low, reflecting stronger phonon scattering that can arise from defects, lattice imperfections, grain boundaries, and anharmonic phonon–phonon interactions. The initial increase in κₗ, up to 600–700 K for most samples, is typical of crystalline materials, where phonon–phonon scattering is weaker at lower temperatures due to reduced thermal agitation. At higher temperatures, however, phonon scattering increases due to enhanced anharmonic interactions and possibly the onset of phonon–impurity scattering in doped systems, leading to a plateau or even a decrease in κₗ. TiFe₂Sn shows stronger phonon scattering, evidenced by a consistently lower κₗ when compared to doped compounds, indicating that phonon transport is inhibited, probably by the simpler crystal structure with fewer defects. Hf doping enhances κₗ because it introduces heavier atoms into the lattice, which changes the phonon scattering, reduces the phonon mean free path by changing the vibrational modes, and introduces a degree of mass fluctuation, which can increase scattering at lower temperatures. In contrast, Y- and In-doped samples show moderate κₗ values, possibly due to different phonon scattering effects.

4. Materials and Methods

Stoichiometrically weighted chemical elements were arc-melted in an inert atmosphere, with the nuggets being flipped and remelted several times to ensure a good sample homogeneity. The resulted nuggets were manually crushed into powders and sintered by the spark plasma method (SPS) for 10 min at 1173 K and an applied pressure of 50 MPa. Disks of about 2 cm in diameter and 1.5 mm thick were obtained and then cut into suitable shapes for measurement. The density of the disk-shaped samples was measured by the Archimedes method.
Examination of the microstructure and quantification of the chemical composition of the samples were carried out using a scanning electron microscope (SEM) (Bruker Evo 50 XVP, Waltham, MA, USA) with an energy dispersive X-ray (EDX) detector (Carl Zeiss NTS, Oberkochen, Germany). The final composition of the samples was determined by averaging the results of the EDX analysis in four different points of the samples. The structural investigation by powder X-ray diffraction at room temperature (RT) was performed using a Bruker D8 Advance diffractometer configured in Bragg–Brentano geometry (Cu Kα radiation) and equipped with a lithium fluoride (LiF) monochromator. Rietveld XRD pattern analysis was performed using FullProf Suite (version 5.1) software.
Low temperature magnetic properties were measured between 1.8 K and 300 K using a superconducting quantum interference device (SQUID) magnetometer (Quantum Design, San Diego, CA, USA) under applied magnetic fields of up to 7 T. High temperature transport properties were measured under argon flux using a Nemesis SBA 458 (Netzsch, Selb, Germany) system (electrical resistivity and Seebeck coefficient) and an LFA-457 (Netzsch) laser flash instrument (thermal diffusivity), between RT and 900 K, with accuracies of about ±2% and ±3%, respectively.

5. Conclusions

Polycrystalline samples based on TiFe2Sn with substitutions at the Ti and Sn sites with p-type or isoelectronic elements have been synthesized by arc melting and SPS. At low doping levels, the samples are single phase with compositions close to the calculated one, while at higher doping levels, secondary phases segregate, especially in Hf0.25Ti0.75Fe2Sn. The anti-site disorder as well as the Fe:Ti non-stoichiometry affect the sample properties, leading to the appearance of weak ferromagnetic ordering, which shows a specific behavior for each type of substitutional atom. They also affect the electrical conductivities of the samples, leading to significantly higher values in Hf-substituted compounds as opposed to Y-substituted compounds. The Seebeck coefficients do not agree with the predicted values, but a slight enhancement is observed for the samples doped with reduced Hf and Sn excess. The total thermal conductivities are high, with an electrical contribution increasing at high temperatures due to thermal carrier activation and a complex contribution from the lattice thermal conductivity influenced by scattering on defects, lattice imperfections, and grain boundaries. Under these circumstances, peak power factor values for Hf0.02Ti0.98Fe2Sn and TiFe2Sn1.05 of 2.69 × 10−4 Wm−1K−2 @ 300 K and 2.52 × 10−4 Wm−1K−2 @ 325 K, respectively, are recorded, representing an increase of about 32% and 24%, respectively, compared to the pristine sample (~2.03 × 10−4 Wm−1K−2 @ 325 K). The maximum ZT value is enhanced by 6.6% for Hf0.02Ti0.98Fe2Sn at 325 K, reaching 0.016 ± 0.002, in comparison to the sample without substitutions, which records 0.015 ± 0.002 at the same temperature.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/inorganics12120322/s1. Figure S1: XRD refinement of Hf0.25Ti0.75Fe2Sn sample. Figure S2: Elemental mapping of a large aria of the Hf0.25Ti0.75Fe2Sn sample. Figure S3: Example of a matrix point analysis for Hf0.25Ti0.75Fe2Sn sample. Figure S4: Example of a secondary phase point analysis for Hf0.25Ti0.75Fe2Sn sample.

Author Contributions

Conceptualization, B.P. and A.G.; methodology, B.P.; software, B.P.; validation, I.A., M.G. and A.G.; formal analysis, B.P.; investigation, I.A. and M.G.; resources, A.G.; data curation, B.P.; writing—original draft preparation, B.P.; writing—review and editing, B.P. and A.G.; visualization, M.G.; supervision, A.G.; project administration, B.P.; funding acquisition, A.G. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Romanian Ministry of Research, Innovation and Digitalization through the Core Program PN23080303, Contract No. 28N/12.01.2023.

Data Availability Statement

The original contributions presented in this study are included in the article/supplementary material. Further inquiries can be directed to the corresponding author.

Acknowledgments

The authors acknowledge the Romanian Ministry of Research, Innovation and Digitalization for financial support through the Core Program PN23080303 (Contract No. 28N/12.01.2023).

Conflicts of Interest

The authors declare no conflicts of interest.

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Inorganics 12 00322 g001
Figure 1. (a) X-ray diffractograms of TiFe2Sn with substitutions and a Rietveld fit for TiFe2Sn (bottom). (b) SEM micrographs on a broken piece of TiFe2Sn (left) and on a polished surface of Ti0.75Hf0.25Fe2Sn (right).
Figure 1. (a) X-ray diffractograms of TiFe2Sn with substitutions and a Rietveld fit for TiFe2Sn (bottom). (b) SEM micrographs on a broken piece of TiFe2Sn (left) and on a polished surface of Ti0.75Hf0.25Fe2Sn (right).
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Figure 2. Temperature dependence of the magnetic susceptibility in 1 kOe (a) and magnetic field dependence of magnetization at 2K (b) in TiFe2Sn with substitutions.
Figure 2. Temperature dependence of the magnetic susceptibility in 1 kOe (a) and magnetic field dependence of magnetization at 2K (b) in TiFe2Sn with substitutions.
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Figure 3. Temperature dependence of electrical conductivity (σ), Seebeck coefficient (S) and power factor (PF) in TiFe2Sn with substitutions at Ti site (a) and Sn site (b).
Figure 3. Temperature dependence of electrical conductivity (σ), Seebeck coefficient (S) and power factor (PF) in TiFe2Sn with substitutions at Ti site (a) and Sn site (b).
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Figure 4. Temperature dependence of the total thermal conductivity (κ), electronic contribution (κe), and phonon contribution (κL) of the TiFe2Sn system with substitutions.
Figure 4. Temperature dependence of the total thermal conductivity (κ), electronic contribution (κe), and phonon contribution (κL) of the TiFe2Sn system with substitutions.
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Figure 5. Temperature dependence of the figure of merit.
Figure 5. Temperature dependence of the figure of merit.
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Table 1. X-ray diffraction refinement results for TiFe2Sn samples.
Table 1. X-ray diffraction refinement results for TiFe2Sn samples.
SampleExtra Phases
(XRD)		a (Å)DensityGoF *
Theoretical (g/cm3)Experimental
(g/cm3)		Relative (%)
TiFe2Sn 6.062 (2)8.0087.66295.682.2
TiFe2Sn1.05 6.061 (7)8.0727.43392.082.2
TiFe2Sn0.99In0.01 6.061 (8)7.9256.96187.832
TiFe2Sn0.98In0.02 6.062 (7)8.0267.01187.352
Hf0.02Ti0.98Fe2Sn 6.066 (0)8.6957.66288.121
Hf0.25Ti0.75Fe2Sn (80.6%)HfFe2 (17.1%)
Hf (2.3%)		6.075 (2)8.8468.51896.292.4
Y0.02Ti0.98Fe2Sn 6.061 (5)8.1757.51491.912.1
* Goodness of fit.
Table 2. Magnetic data (effective moment, Curie–Weiss temperature, saturation magnetization) for TiFe2Sn system.
Table 2. Magnetic data (effective moment, Curie–Weiss temperature, saturation magnetization) for TiFe2Sn system.
Sampleμeff (μB)θCW (K)MS (μB/f.u.) @ 2K
TiFe2Sn2.868223.960.179
TiFe2Sn0.98In0.022.113243.820.236
Ti0.98Hf0.02Fe2Sn2.733243.790.229
Ti0.75Hf0.25Fe2Sn10.54352.211.157
Ti0.98Y0.02Fe2Sn1.709237.50.224
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Popescu, B.; Assahsahi, I.; Galatanu, M.; Galatanu, A. Effects of Ti and Sn Substitutions on Magnetic and Transport Properties of the TiFe2Sn Full Heusler Compound. Inorganics 2024, 12, 322. https://doi.org/10.3390/inorganics12120322

AMA Style

Popescu B, Assahsahi I, Galatanu M, Galatanu A. Effects of Ti and Sn Substitutions on Magnetic and Transport Properties of the TiFe2Sn Full Heusler Compound. Inorganics. 2024; 12(12):322. https://doi.org/10.3390/inorganics12120322

Chicago/Turabian Style

Popescu, Bogdan, Ilhame Assahsahi, Magdalena Galatanu, and Andrei Galatanu. 2024. "Effects of Ti and Sn Substitutions on Magnetic and Transport Properties of the TiFe2Sn Full Heusler Compound" Inorganics 12, no. 12: 322. https://doi.org/10.3390/inorganics12120322

APA Style

Popescu, B., Assahsahi, I., Galatanu, M., & Galatanu, A. (2024). Effects of Ti and Sn Substitutions on Magnetic and Transport Properties of the TiFe2Sn Full Heusler Compound. Inorganics, 12(12), 322. https://doi.org/10.3390/inorganics12120322

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