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Bismuth antimony telluride (Bi0.5Sb1.5Te3) is a ternary compound with good thermoelectric properties at near room temperature. In this research, Bi0.5Sb1.5Te3 powders were hydrothermally synthesized at different temperatures (100, 150, 190, and 230°C) for 24 h. The deposition procedure of Bi0.5Sb1.5Te3 thin films was done by using thermal evaporation. The phases and microstructures of powders and thin films were investigated by x-ray diffraction and field emission scanning electron microscopy. Moreover, the size distribution of powders was investigated using a particle size analyzer. The phase and microstructural results of the different synthesized powders confirmed that the Bi0.5Sb1.5Te3 thin film prepared by powder synthesis at 150°C for 24 h is the best choice for manufacturing with good thermoelectric properties because of its nano-sized grains and high purity. The results showed that the Bi0.5Sb1.5Te3 thin film fabricated by powders synthesized at 150°C has a single rhombohedral phase with a good semiconductor performance. The results of thermoelectric tests confirmed that the Bi0.5Sb1.5Te3 thin film fabricated using a hydrothermal method and thermal evaporation deposition approach shows a high Seebeck coefficient (183.5 μV/K) and low electronic thermal conductivity (1.32 × 10−4 W/m k−1) at 298 K. Besides, the power factor values of 0.7, 2.59 and 2.9 μW/cm K−2 were obtained at 298, 373 K and 473 K, respectively.

Thermodynamic assessment of the ternary system B-Hf-Zr has been conducted by modeling the Gibbs energy of all individual phases using the CALPHAD (CALculation of PHAse Diagrams) approach. There is no ternary compound in this system. The individual solution phases, i.e., liquid, (βHf,βZr), HfB and (Hf,Zr)B2 have been modeled. The modeling covers the whole composition and temperature ranges. The Gibbs energies of HfB2 and HfB in the B-Hf system were reassessed using the two-sublattice models (B,Hf)1(B,Hf)2 and (Hf)1(B,Hf)1, respectively. A set of self-consistent thermodynamic parameters for the B-Hf-Zr system was obtained by considering the phase diagram data in the ternary system. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information was satisfactorily accounted for by the present thermodynamic description. The liquidus projection and reaction scheme of the B-Hf-Zr system are also presented.

The effects of joining temperature (TJ) and time (tJ) on microstructure of the transient liquid phase (TLP) bonding of GTD-111 superalloy were investigated. The bonding process was applied using BNi-3 filler at temperatures of 1080, 1120, and 1160 °C for isothermal solidification time of 195, 135, and 90 min, respectively. Homogenization heat treatment was also applied to all of the joints. The results show that intermetallic and eutectic compounds such as Ni-rich borides, Ni−B−Si ternary compound and eutectic-γ continuously are formed in the joint region during cooling. By increasing tJ, intermetallic phases are firstly reduced and eventually eliminated and isothermal solidification is completed as well. With the increase of the holding time at all of the three bonding temperatures, the thickness of the athermally solidified zone (ASZ) and the volume fraction of precipitates in the bonding area decrease and the width of the diffusion affected zone (DAZ) increases. Similar results are also obtained by increasing TJ from 1080 to 1160 °C at tJ=90 min. Furthermore, increasing the TJ from 1080 to 1160 °C leads to the faster elimination of intermetallic phases from the ASZ. However, these phases are again observed in the joint region at 1180 °C. It is observed that by increasing the bonding temperature, the bonding width and the rate of dissolution of the base metal increase. Based on these results, increasing the homogenization time from 180 to 300 min leads to the elimination of boride precipitates in the DAZ and a high uniformity of the concentration of alloying elements in the joint region and the base metal.

Cd1−xZnxTe (CZT)-based matrices have highest absorption capabilities and tunable band gap, so it can be utilized as the central most significant photon absorption layer. In this research, we have briefly investigated the effect of annealing dynamics over the phosphorus ion (P+) implanted Cd1−xZnxTe on different stoichiometric ratios. The P+ ions are introduced at 800 keV in order to tailor/tune the electro-optical characteristics of said ternary compound matrix for its utilization as an active medium in photovoltaic and related application. In this specific study, the annealing dynamics of P+ implanted Cd1−xZnxTe scheme have been studied, and three temperature ranges were chosen ~ 300, 350, and 400 °C for such purpose. The impact of annealing behavior has been envisaged by electrical and electro-optical characterization techniques, i.e., current–voltage (I–V), activation energy, charge-based deep-level transient spectroscopy (Q-DLTS) and transient of photo-voltage (TPV). From Q-DLTS study, one has obtained different defect levels that may limit the overall performance of the as-implant CZT matrix. By adopting RTA process, the damage content in form of trap levels has shifted themselves near premises to their respective band edges i.e., for as-implant cases, the trap level placed near the Fermi level and when the RTA process subjected the trap levels localized themselves to the close proximity to either of its band edge (valance/conduction level), e.g., the trap level of CdTe shift from 0.123 to 0.005 eV, i.e., near the valance band edge which may enhance the trap characteristics. Also, the activation energy and transient of photo-voltage analysis direct the physical importance of RTA process because this process may provide significant increase of carrier’s generation by reduction in activation energy and elevation of photo-voltage by utilizing the appropriate annealing sequence to subject CZT crystal. The TPV analysis of Cd0.75Zn0.25Te sample shows higher extent of physical voltages ~ 63 mV at 400 °C annealing sequences, whereas for as-implant case provides just ~ 10 mV.

The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the toxicity of their cathodes. Materials constituted of ternary lithiated oxide compounds are a successful alternative to cobalt-rich cathodes. The main disadvantage of ternary compound materials (TCM) is that the maximum amount of electrical charge is only achieved at high redox potentials, a limiting factor if we consider the current development in electrolyte technology. In this work, we investigated the influence of sputtering deposition parameters on the charge capacity of TCM thin films, restraining their electrochemical potential to conventional values. To do so, we analyzed the impact that small changes in crystalline and morphological structures have on the charge capacity at low cell potentials. For this, we performed the RF magnetron sputtering of TCM thin films, and carried out a factorial design of experiments to investigate their electrochemical properties, while limiting the charging potential to 4.20 V vs. Li|Li+. The films were deposited onto a rigid and conductive substrate with different parameters (power and pressure at room temperature). Electrochemical results showed that the discharge capacity is strongly influenced by the deposition parameters, reaching 250 mAh g− 1 even at 4.20 V vs. Li. This value is superior to the ones of the conventional cobalt cathode and the bulk ternary electrode. Both deposition parameters exhibited a synergic dependency, which means that they need to be simultaneously varied for a response optimization. The discharge capacity of the analyzed samples was highly affected by the surface morphology of the film and its crystallographic properties, and not by its elemental composition. High discharge capacity was obtained without additional thermal treatments, which favors the manufacture of films over polymeric substrates for future electronic applications.

Desulfurization ability and hydration resistance of CaO-MgO mixture were studied by comparing CaO-MgO, CaO and MgO rods. In desulfurization experiment, Ni-base superalloy and NiS powder were melted together, and each rod was held in the melt for a prescribed time under 1600 °C. S content in the alloy was lower in CaO-MgO desulfurization than that in CaO desulfurization in every holding time up to 300 seconds. Almost no desulfurization effect was confirmed in MgO. From EPMA and XRD analyses, it is considered that CaO-Al2O3-MgO ternary compound and CaS were generated and coexisted in the CaO-MgO rod during the desulfurization process. In the CaO-MgO desulfurization, the compound contained MgO as its component, and that decreased the liquidus temperature of the compound. Therefore, it is considered that the fraction of liquid increased, and the effective diffusion coefficient of S in the compound was larger than in the CaO desulfurization. In hydration experiment, each rod was maintained in an enclosed vessel with weighing paper and a cup with water for a certain period. The mass increasing ratio of the CaO-MgO was almost equal to that of the CaO. From the above, it is clear that CaO-MgO is a better desulfurization agent than CaO.

Demand for simple and effective gas sensing sensors is growing rapidly due to the growing threat of triethylamine (TEA). Semiconductor tin oxide (SnO2) is one of the most widely used sensing materials for metal oxide gas sensors. In recent years, a lot of binary ternary compound researches have been carried out. In this paper, five different SnO2 samples were synthesized by simple synthesis method to understand the internal relationship and obtain different gas sensing characteristics. Based on the low temperature nitrogen adsorption tests and the atomic arrangement model, it can be inferred that different exposed surfaces play a key role in TEA sensing properties. In addition, the TEA sensing activity relationship of SnO2 exposed crystal faces is proposed as listed: (200) > (101) > (110).

The magnesium-rich intermetallic ternary compound NdNiMg15 in space group P-4/nmm (no. 26) space group in trigonal phase is studied theoretically using hybrid functional theory (HP-B3PW91) in the density functional theory (DFT) framework. The calculation results are in good agreement with experimental data. The metallic nature of the compound is estimated from the electronic properties. The magnetic as well as metallic character of the compound is due to the Nd 4f electrons. The title compound exhibits good conductivity as revealed by the thermoelectric analysis. The magnetic phase of the material indicates its stability within the G-type antiferromagnetic phase (G-AFM), governed by direct Nd–Nd exchange interactions with a magnetic moment of 3.57µB/Nd per unit cell. The AFM phase of the studied compound is also confirmed by post-DFT measurements at TN = 8.15 K as well as θ = −2.5 K. The antiferromagnetic nature of this compound could enable its use in magnetic probes to read data stored in antiferromagnetic moments while leaving them unaffected by disturbing magnetic fields.

A new ternary compound, Al2Fe3Nd, was prepared via arc melting using a non-consumable tungsten electrode under an argon atmosphere with subsequent annealing at 923 K for 30 days. Its crystal structure was determined using the Rietveld refinement of powder X-ray diffraction data. The results show that Al2Fe3Nd has a hexagonal structure in a space group of P6/mmm (No. 191). It is isostructural with the Al2.5Ni2.5Y compound. It has lattice parameters of a = 8.8625(3) Ǻ and c = 4.1475(2) Ǻ with a calculated density Dcalc = 6.460 g/cm3. The residual factors converge to Rp = 0.0946 and Rwp = 0.1214. In the temperature range of 2–500 K, magnetic susceptibility has been measured. The magnetic susceptibility of Al2Fe3Nd follows the Curie–Weiss law in the temperature range of 410–500 K. The effective magnetic moment μeff and paramagnetic Curie temperature θP were estimated to be 8.59 μB and 399.8 K, respectively. The saturation magnetic moment and magnetic hysteresis loop for the compound were measured under room- and low-temperature conditions. The measurements indicate that the saturation magnetization moment declines with increasing temperature, and the compound is ferrimagnetic in the analytical temperature range of 2–300 K.

Zinc tin phosphide (ZTP) has attracted recent research interest as a low-cost light sensing material, alternative to III–V and II–III-based compounds, for photo-detector and solar cell applications. In this study, a versatile chemical route for the synthesis of ZTP nanoparticles starting from commercially available alkyl-zinc and tin, alkyl-phosphoramides and trioctylphosphine at a relatively low temperature of 160 °C is reported, which can straightforwardly be extended to other analogous II–IV-P2 group ternary compounds. The particles displayed high stability and can be deposited as layers with few monolayers of thickness. The structural and chemical analysis revealed that the particles are of sub-10 nm size with chalcopyrite structure and ZnSn-phosphide composition. The particles exhibited optical band-gap in the range of 1.65–1.75 eV and a broadband photo-response in the visible wavelengths (400–700 nm) with excellent response to red light.

Dark current is the main factor that influences photodiode performance. It should be minimal to reduce noise and ensure a high level of photoelectric parameters. In order to identify the predominant causes of generation–recombination in photodiodes based on a mercury–cadmium–tellurium (MCT) ternary compound in the given voltage range, a calculation model is proposed for dark currents caused by fundamental and other current mechanisms. The components of dark current in photodiodes based on MCT heterostructures grown by molecular beam epitaxy (MBE) and liquid-phase epitaxy (LPE) methods are determined in the reverse bias voltages range from 0 to 40 mV. In the range from 0 to 20 mV, these characteristics are reduced to the diffusion component. When the reverse bias voltage exceeds 30 mV, an increase in the Shockley–Read–Hall (SRH) generation–recombination current and tunneling current through trap levels in the band gap is observed.

Fundamental thermodynamic properties of the synthetic analog of the famatinite mineral - Cu3SbS4 were studied on the basis of electromotive force (EMF) measurements. The EMF of the concentration chains relative to the Cu electrode with a solid electrolyte was measured for the alloys from the Cu3SbS4 + Sb2S3 + S phase region at 300-380K temperature interval. Based on measurement data, the relative partial thermodynamic functions of copper in alloys, the standard thermodynamic functions of formation, as well as, the standard entropy of the Cu3SbS4 ternary compound were calculated for the first time.

A ternary compound of Li6NiNb2O9 with a rock-salt structure was prepared by the conventional mixed oxide route, and after the ceramic preparation processes, its microwave dielectric properties were investigated. Ceramics with a single phase and a rock-salt crystal structure can be obtained under our optimized sintering conditions, and a disordered rock-salt structure for Li6NiNb2O9 compound can be confirmed by the Rietveld method. Relatively dense microstructures can be obtained under the sintering conditions of 1080°C/2.0 h, with microwave dielectric properties of e = 13.5, Q × f = 20,600 GHz (9.4 GHz) and τf = −33.9 ppm/°C. Although decomposition of such phase occurred when high sintering temperature was applied (> 1100°C), the density and microwave dielectric properties of the ceramics showed anomalous increases.

Phase equilibria during solidification in the Al-Cr-Co system in the range of compositions 0-70 at.% Al were studied using optical microscopy, scanning electron microscopy, electron probe microanalysis, differential thermal analysis and x-ray diffraction. Solidus and liquidus surfaces, a melting diagram as their superposition, a Scheil diagram for solidification, as well as series of isopleths were constructed for the first time. Solid solutions based on Cr, αCo, Cr5Al8 (γ3 and γ1 phases), CoAl, Co2Al5 binary compounds and the ternary compound τ5 take part in phase equilibria. The monoclinic ternary compound τ5 forms by peritectic reaction L + γ1 + Co2Al5 ↔ τ5 at 1065 °C. Four invariant four–phase reactions and one invariant three–phase reaction involving liquid take place at 1280, 1175, 1110, 1065 and about 1480 °C, respectively. Isopleths 10, 20, 30 and 40 at.% Al as well as 40 at.% Cr demonstrate peculiarities of the phase diagram.

The isothermal sections of the Al–Cr–Ta ternary system at 1000 and 1200 °C have been determined by means of electron probe microanalysis and x-ray diffraction. The results show that eleven and nine three-phase regions are determined in the isothermal sections at 1000 °C and 1200 °C, respectively. No ternary compound exists at both two isothermal sections. The addition of Cr makes the Al69Ta39 phase be stable at 1000 °C. The Cr2Ta(HT) phase has a large composition range at both two isothermal sections. The experimental information obtained in the present work could be significant for alloy design and the complement of the thermodynamic database.

The 450 and 600 °C isothermal sections of the Ni-V-Zn ternary system have been investigated through Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and x-ray Diffraction (XRD) technique. Eight three-phase regions have been confirmed at the 450 °C section and nine three-phase regions exist at the 600 °C one. Experimental results indicate that it is difficult for Ni to dissolve in VZn3 and V4Zn5. The solid solubilities of V in γ(Ni2Zn11) and β1(NiZn) are 1.4 and 3.7 at.% at 450 °C, respectively, while V in γ and β1 are 2.5 and 4.0 at.% at 600 °C, respectively. The solid solubilities of Zn in Ni2V7, σ(Ni2V3), Ni2V and Ni3V are 0.5, 4.7, 2.3 and 2.6 at.% at 450 °C as well as 0.5, 9.5, 2.2 and 2.8 at.% at 600 °C, respectively. No ternary compound has been found in this work.

Ternary compound CuSbSe2-alloyed PbTe, CumPb100SbmTe100Se2m (CLAST), presents outstanding n-type thermoelectric transport behavior and features hierarchical Cu-based precipitates and interstitials that can balance phonon and carrier transport. Results show that a small amount of CuSbSe2 (∼3%) alloying in CLAST can realize a room-temperature carrier concentration of ∼1.7 × 1018 cm−3 and then optimize the power factor, and simultaneously precipitate out embedded Cu-based nanostructures in the matrix to lower the lattice thermal conductivity. Additionally, extra Cu atoms adding in CLAST can form interstitials and further improve both the carrier concentration to ∼3.0 × 1018 cm−3 and carrier mobility to ∼1227.8 cm2 V−1 s−1 at room temperature, which benefits a maximum power factor of ∼20.0 μW cm−1 K−2 in Cu3.3Pb100Sb3Te100Se6. Moreover, the Cu interstitials together with massive Cu-based nanoprecipitates can strongly scatter a wide set of phonons, and largely lower the lattice thermal conductivity to ∼0.44 W m−1 K−1 in Cu3.4Pb100Sb3Te100Se6 at 623 K. Finally, these Cu-based hierarchical structures in CLAST samples can synergistically optimize the phonon and carrier transport properties and contribute to a high ZT of ∼0.5 at 300 K and a peak ZT of ∼1.4 at 723 K. A remarkably high ZTave of ∼0.94 at 300–723 K is achieved in Cu3.3Pb100Sb3Te100Se6 due to high ZT values in the low temperature range, outperforming other high-performance n-type PbTe-based thermoelectric materials.

The thermodynamic modeling of the ternary system C-Cr-Zr has been obtained by modeling the Gibbs energy of all individual phases using the CALPHAD (CALculation of PHAse Diagrams) approach. There is no ternary compound in this system. The liquid is modeled as a substitutional solution phase, while the solid solution phases including ZrC, (αZr), (βCr), (βZr), Cr3C2, Cr7C3, Cr23C6, C14, C15 and C36 are described by sublattice models. The modeling covers the whole composition and temperature ranges. A set of self-consistent thermodynamic parameters for the C-Cr-Zr system is obtained by considering the phase diagram data in the ternary system. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information is satisfactorily accounted for by the present thermodynamic description. The liquidus projection and reaction scheme of the C-Cr-Zr system are also presented.

Cathodic electrodeposition technique has been successfully used to achieve the growth of polycrystalline CdMnTe ternary compound thin films at different cathodic potentials. The choice of various cathodic potentials used in this work was made from the cyclic voltammogram results. The CdMnTe thin films were electroplated from electrolytes containing CdSO4, TeO2 and MnSO4·H2O in an acidic aqueous medium. The electrodeposition was carried out on glass/fluorine-doped tin oxide {FTO} substrates. The structural, optical, morphological and electrical properties of the CdMnTe thin films were studied using X-ray diffraction (XRD), UV–Vis spectroscopy, scanning electron microscopy (SEM), current–voltage (I–V) characteristics and photo-electro-chemical (PEC) cell measurements respectively. The materials investigated in this work were explored under three different conditions namely: as-deposited (AD), heat-treated ordinarily in air (HT) and heat-treated in air in the presence of CdCl2 surface treatment (CC). Results from the XRD showed that the electrodeposited films are polycrystalline with the presence of CdTexOy and CdMnTe peaks. The electroplated films have cubic crystal structures and the preferred orientation was found to be along the (111) plane. The optical energy bandgaps of the thin films were found to be deposition potential dependent. Electrical conductivity types namely p- and n-type conductivity were also obtained at different cathodic potentials using photo-electro-chemical cell measurement technique for as-deposited and heat-treated materials.

Equilibrated alloys were characterized using SEM/EDX and XRD methods to identify the Co-Nb-Ni phase equilibria at 1100 °C and 900 °C. The isothermal section at 1100 °C was re-constructed and the partial phase relationships at 900 °C were further validated. The crystal structure of the ternary compound τ was proved to be of the Mg3Cd type with Pearson symbol hP8 and space group P63/mmc. The addition of nickel can increase the phase stability of Co7Nb2. The Co-Nb, Ni-Nb, and Co-Nb-Ni systems were assessed using the CALPHAD (CALculation of PHAse Diagram) method. The present experimental and calculated results can be used as a reference for developing and designing Co/Ni-based intermetallics and superalloys.

Using CALPHAD method, the Al-Zr, Al-Li and Al-Li-Zr systems have been reassessed based on the latest experimental phase relations from literatures and the first-principle calculation of the formation enthalpy for ternary compound T1(AlLi2Zr) in this work. The excess Gibbs energies of solution phases, including liquid, bcc, fcc and hcp, were expressed by the Redlich–Kister polynomial. The stoichiometric compounds, i.e. Al4Zr5, Al3Zr5, AlZr2, AlZr3, Al2Li3, Al4Li9 and T1(AlLi2Zr), were modeled as stoichiometric model and the non-stoichiometric compounds, i.e. Al3Zr, Al2Zr, Al3Zr2, AlZr, Al3Zr4, Al2Zr3, AlLi2 and T2(AlLix+yZr5−x), were described with different sublattice models. Finally, a set of reasonable thermodynamic parameters for Al-Li-Zr ternary system have been obtained, which notes a clear improvement on the self-consistency. The calculated isothermal section at 470 K of Al-Li-Zr system was in reasonable agreement with the experimental one.

The diamond-like compound Cu3PSe4 with low lattice thermal conductivity is deemed to be a promising thermoelectric material, which can directly convert waste heat into electricity or vice versa with no moving parts and greenhouse emissions. However, its performance is limited by its low electrical conductivity. In this study, we report an effective method to enhance thermoelectric performance of Cu3PSe4 by defect engineering. It is found that the carrier concentrations of Cu3−xPSe4 (x = 0, 0.03, 0.06, 0.09, 0.12) compounds are increased by two orders of magnitude as x > 0.03, from 1 × 1017 to 1 × 1019 cm−3. Combined with the intrinsically low lattice thermal conductivities and enhanced electrical transport performance, a maximum zT value of 0.62 is obtained at 727 K for x = 0.12 sample, revealing that Cu defect regulation can be an effective method for enhancing thermoelectric performance of Cu3PSe4.

Interaction between the components in the Ho-Fe-Sn ternary system was studied using X-ray diffractometry, metallography and electron microprobe analysis. Isothermal section of the phase diagram was constructed at 670 K over the whole concentration range. Component interaction in the Ho-Fe-Sn system at 670 K results in the existence of one ternary compound HoFe6Sn6 which crystallizes in the YCo6Ge6 structure type (space group P6/mmm, a=0.53797(2), c= 0.44446(2) nm). The interstitial-type solid solution HoFexSn2 (up to 8 at.% Fe) based on the HoSn2 (ZrSi2-type structure) binary compound was found. Solubility of Sn in the HoFe2 binary (MgCu2 structure type) extends up to 5 at. %.

The Pb-Se-Sn ternary system is of interest to thermoelectric applications. Nevertheless, no phase diagram exists for the entire compositional regime at any temperature. Ternary Pb-Se-Sn alloys are equilibrated at 350°C and 500°C, and their equilibrium phases are determined. The isothermal sections of the equilibrium Pb-Se-Sn phase diagram at 350°C and 500°C are proposed based on the phase diagrams of the three constituent binary systems and ternary phase equilibria results in the literature and those determined in this study. No ternary compound is found. The phase relationships are similar at 350°C and 500°C. At both temperatures, binary compounds, α-PbSe and γ-SeSn, have very significant ternary solubility, but the ternary solubility of Pb in the Se2Sn phase is negligible. There are still unresolved questions about the type and shape of the liquid phase at the Se corner.

Phase equilibria in the Co–Fe–La system were studied using differential thermal analysis (DTA), X-ray diffraction analysis, scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). Liquidus and solidus projections and a melting diagram for this system over the whole concentration range and a Scheil diagram for solidification were constructed. The ternary compound (Co,Fe)17La2 (τ) (Th2Zn17-type structure) forms by peritectic reaction L + (γCo,Fe) + Co13La ⇄ τ at 978 °C. This ternary compound is located along the isoconcentrate of 11 at.% La and extends from 45.8 to 79.3 at.% Co. The Co13La phase has the widest homogeneity region and dissolves up to 43.3 at.% Fe. The solubilities of Fe in Co5La, Co7La2, Co19La5, and Co3La2 were established to be 10.3, 9.2, 4.7, and 3.2 at.%, respectively. The solubility of Fe in Co1.7La2 and CoLa3 according to EPMA does not exceed 1 at.%. The maximum solubility of La in (γCo,Fe) and (αCo,Fe) is determined to be less than 1 at.%.

The phase relationships of the Ce-Pr-Fe ternary system at 600 °C were experimentally investigated using equilibrated alloys and diffusion junction samples with the use of electron probe microanalysis, x-ray diffraction, and scanning electron microscopy. The isothermal section of the Ce-Pr-Fe system at 600 °C consists of 7 single-phase, 11 two-phase, and 5 three-phase regions. No ternary compound was found. The PrFe2 phase was observed in both ternary alloys and diffusion samples at normal pressure. The solid solubility of Ce in PrFe2 and Pr2Fe17 is 1.76 and 3.75 at.%, respectively. The solid solubility of Pr in CeFe2 and Ce2Fe17 is 13.21 and 0.77 at.%, respectively.

The phase relationships in the Zn-Al-Ti system at 450 and 600 °C were experimentally determined using equilibrated alloys method. The specimens were investigated by means of scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffractometry. Eleven and eight three-phase regions are confirmed in the 450 and 600 °C isothermal sections, respectively. The Ti2Al5 which only exists at high temperature (990-1199.4 °C) in Ti-Al binary system is confirmed in two isothermal sections due to the dissolution of zinc. The T phase is confirmed as a ternary compound rather than an extension phase of TiZn3 at 450 °C. The T2 phase is a new ternary phase stable at 450 and 600 °C in Zn-Al-Ti ternary system.

Phase transformations in the Zr-Co-Sn ternary system have been studied at crystallization using differential thermal analysis (DTA), x-ray diffraction analysis, scanning electron microscopy, and electron probe microanalysis. The solidus surface of this system over the whole concentration range is constructed for the first time, involving 20 three-phase regions. Four ternary compounds, viz. ZrCo2Sn (τ1), ZrCoSn (τ2), Zr6Co1.65Sn1.35 (τ3), and Zr5Co6Sn18 (τ4), are confirmed. It is shown that they exist at the solidus temperatures. The crystal structure of the compound τ4 is first established as Tb5Rh6Sn17-type (cF116-Fm-3m) with lattice parameter a =13.376(6) A. Only one ternary compound (ZrCo2Sn, τ1, Heusler phase) has a rather wide homogeneity range at solidus temperature (43.5–50 at.% Co along the 50Zr50Sn-Co ray). Binary compounds Zr5Sn3+x and ZrCo2 dissolve up to 9 at.% Co and 14.5 at.% Sn, respectively. All other compounds are practically linear phases. The above six phases define the character of the solidus projection, taking part in all three-phase equilibria, except for those with participation of Sn.

Phase relationships in the Nd-Ce-Fe ternary system at 773 K have been investigated mainly by x-ray diffraction and scanning electron microscopy with energy disperse spectroscopy techniques. The isothermal section consists of 6 single-phase regions, 7 two-phase regions and 3 three-phase regions. No ternary compound is observed in this system. Nd2Fe17 and Ce2Fe17 are found to form a continuous solid solution (Nd,Ce)2Fe17, and the solubilities of Ce in Nd5Fe17 and Nd in CeFe2 are determined.

In this study, the phase equilibria of the Cr-Mo-Hf ternary system at 1100 and 1300 °C were experimentally investigated by means of back-scattered electron, electron probe microanalysis and x-ray diffraction. The two C15 phases (α(HfMo2) and α(HfCr2)) link up with each other from Mo-Hf side to Cr-Hf side across the isothermal sections both at 1100 and 1300 °C. The isothermal section at 1300 °C consists of one three-phase region and three two-phase regions, while no ternary compound is found. One single-phase region of bcc(βHf) not connected with Mo-Hf binary boundary is found unexpectedly at 1100 °C, which results in the appearance of two extra three-phase regions.

The 600 and 800 °C isothermal sections of the Al-Ni-Sn ternary system were determined based on examination of equilibrated alloys by SEM spectroscopy and x-ray powder diffraction. Nine and Six three-phase regions exist in the Al-Ni-Sn system at 600 and 800 °C respectively. All the Al-Ni and Sn-Ni binary compounds except Al3Ni4 were confirmed at 600 °C, no ternary compound exists in Al-Ni-Sn system. The Ni3Sn2, Ni3Sn and AlNi3 phases show a large solubility of the third element. No ternary compound exists in Al-Ni-Sn system.

To experimentally determine the isothermal sections of Co−Mo−Zn ternary system at 600 and 450 °C, the equilibrated alloy and diffusion couple methods were adopted by using scanning electron microscopy coupled with energy-dispersive spectrometry, X-ray diffractometry and electron probe microanalysis. Experimental results show that there are six three-phase regions on the Co−Mo−Zn isothermal section at 600 °C and nine three-phase regions on the Co−Mo−Zn isothermal section at 450 °C. No ternary compound is found in these two isothermal sections. Both the maximum solubilities of Mo in the Co−Zn compounds (γ-Co5Zn21, γ1-CoZn7, γ2-CoZn13 and β1-CoZn) and that of Zn in e-Co3Mo are no more than 1.5 at.%. The maximum solubilities of Zn in μ-Co7Mo6 are determined to be 2.1 at.% and 2.7 at.% at 600 and 450 °C, respectively. In addition, the maximum solubilities of Co in MoZn7 and MoZn22 are 0.5 at.% and 4.7 at.% at 450 °C, respectively.

The influence of Al on the thermoelectric properties of the half-Heusler (HH) TiNiSn compound is reported. The research combined ab initio Density Functional Theory (DFT) calculations with experimental microstructure evaluation and measurements of the transport properties up to 750 K. It is shown that Al addition to the Ti sub-lattice results in an increase of the absolute value of the Seebeck coefficient and electrical resistivity in polycrystalline TiNiSn, while preserving the n-type behavior of the ternary compound, in addition to a significant reduction of the thermal conductivity. In (Ti0.99Al0.01)NiSn, upon 1% Al substitution of Ti, an improvement of 17% in the thermoelectric figure of merit (0.42 at 723 K) compared to pure TiNiSn was observed. Theoretical lattice thermal conductivity calculations are applied to shed light on the different scattering mechanisms in this class of materials. It is shown that the major contribution to the lattice thermal conductivity reduction is stimulated by the presence of Sn-rich inclusions, in addition to an influence of mass fluctuation scattering due to substitution of Ti by Al. Although it is shown that in the widely applied polycrystalline TiNiSn, an addition of the acceptor Al dopant could not fully compensate n-type electronic active defects (e.g. grain boundaries) for obtaining p-type materials, the currently reported results pave a route for thermoelectric optimization of MNiSn (M = Ti, Ni, Sn) n-type half-Heusler compounds.

Cu1.45Ni1.45Te2 ternary compound was synthesized by solid-state ball-milling method and densified via spark plasma sintering (SPS) and cold-pressing with annealing (CPA) techniques. The effect of densification techniques on the thermoelectric properties was studied. SPS sample showed negative Seebeck coefficient values for the entire temperature range, while CPA sample changed the sign of the Seebeck coefficient above 573 K from n-type to p-type. The electrical conductivity was higher for SPS sample than for CPA sample for the entire temperature range. Hence, SPS sample exhibited 167% increased zT when compared to CPA sample. It is confirmed that the SPS technique is more suitable to obtain a high zT value than the CPA technique for n-type Cu1.45Ni1.45Te2 sample. Also, the effect of carrier concentration was studied and the change in the carrier concentration was done by Se-doping. From a series of thermoelectric measurements, it was found that the undoped sample exhibited a high zT of about 0.004 at 400 K and the Se-doped sample exhibited a zT of 0.001 at 750 K. It means that Se-doping mainly influences the shifting of the operating temperature of TE performance from room temperature range to mid-temperature range. The formation of n-type TE material was realized due to the delocalization of electron density on Te-ions, which compensate the Cu-vacancies resulting in the n-type conduction behaviour. Se-doping modifies the reaction of Te-ions with cations affecting the delocalization of electron density, which shifts the conduction type from n-type to p-type behaviour.

U3Si2C2 is expected to be a new nuclear fuel as a ternary compound of uranium, silicon and carbon. However, the relevant research on U3Si2C2 under accident conditions is rarely reported. Hence it is necessary to explore the service behavior of the potential U-Si-C ternary nuclear fuel in extreme environments. In this work, the structural characteristics, electronic behaviors and mechanical properties of U3Si2C2, such as stable crystalline structures, density of states, charge distributions, electron localization function, electronic thermal conductivity and elastic modulus under extreme high pressure are calculated by density functional theory. The calculation results show that the lattice volume sharply increases when the external stress reached 9.8 GPa. Ionic and metallic nature coexist as to the bonding characteristics of U3Si2C2, and the ionic takes the dominant position in bonding. The toughness of U3Si2C2 is predicted to be better compared to U3Si2. Our theoretical investigation may help with the application of U3Si2C2-based fuel and the design of ternary uranium fuels.

CuSbSe2 is emerging as an alternative absorber for thin-film photovoltaics owing to its intrinsic p-type conductivity, proper band gap (~ 1.1 eV), high-absorption coefficient (> 104 cm−1) and low cost. Moreover, it is nontoxic and its compositional elements (Cu, Se and Sb) are abundant in the crust of earth. In the present work, Sb2Se3/Cu multilayers were deposited by pulsed laser deposition (PLD) followed by magnetron sputtering (MS). After that, the as-prepared multilayers were annealed in-suit in the MS chamber at different temperatures and times to obtain high-quality CuSbSe2 ternary compound. Five intermetallic compounds were generated in this process, including CuSbSe2, Sb2Se3, CuSe2, Cu2Se and Cu3SbSe3. Besides, it was found out that most CuSbSe2 ternary compound was generated when the as-prepared multilayers were annealed at 420 °C for 10 min. The crystallite size of CuSbSe2 phase increased with elevating annealing temperature, while more holes and gaps occurred when the annealing temperature exceeded 420 °C. The results of energy-dispersive spectrometer indicated the film was highly developed with nearly stoichiometric atomic ratio of 27.91:22.72:49.37 (Cu:Sb:Se). The electrical measurement results revealed the semiconducting nature of the film and gave the conductivity activation energy of 0.26 eV, 0.08 eV and 0.13 eV, respectively. The direct band gap of the annealed film was revealed as 1.13 eV, which fulfilled the Shockley–Queisser requirements for the efficient harvesting of the solar spectrum.

The isothermal section of the Al-Si-Ti ternary system at 550 °C has been determined using scanning electron microscopy, energy dispersive spectroscopy, and x-ray diffraction. Results show that there are 12 three-phase equilibrium regions in the isothermal section of the system. The maximum solubility of Si in Al3Ti is 16.4%, and the solubility of Al and Ti in Si is small. There exists only one ternary compound in the isothermal section with a composition of Al7.1-13.9Ti33.5-34.2Si51.9-59.1.

The influences of Nb-containing oxides and ternary compound in hydrogen sorption performance were investigated. As faster desorption kinetic and lower activation energy were reported by addition of a ternary compound catalyst such as K2NiF6, the influence of KNbO3 on hydrogen storage properties of MgH2 has been investigated for the first time. The MgH2 - KNbO3 composite desorbed 3.9 wt% of hydrogen within 10 min, while MgH2 and MgH2-Nb₂O₅ composites desorbed 0.66 wt% and 3.2 wt% respectively under similar condition. For MgH2 with other Nb-contained catalysts such as Nb, NbO and Nb₂O3, the desorption rate was almost the same as the one registered for as-milled MgH2. The analysis of differential scanning calorimetry (DSC) showed that MgH2-KNbO3 composite started to release hydrogen at ∼335 °C which is 50 °C lower compared to as-milled MgH2 without any additives. The activation energy for the hydrogen desorption was estimated to be about 104 ± 6.8 kJ mol−1 for this material, while for the as-milled MgH2 was about 165 ± 2.0 kJ mol−1. It is believed that Nb-ternary oxide catalyst (KNbO3) showed a good catalytic effect and enhance the sorption kinetics of MgH2.

The fission product strontium (Sr), after generation in the reactor due to fission of 233U, might exist as SrF2 in the molten fluoride medium of molten salt reactor (MSR) using fluoride carrier salts. The high temperature interactions between the strontium fluoride (SrF2) with the fertile fuel component and thorium fluoride (ThF4) leads to form single ternary compound SrThF6(s). The Gibbs energy of formation is the driving force for formation of any compound. In the present study, standard molar Gibbs energy of formation SrThF6(s) has been determined using an e.m.f. technique using CaF2(s) as solid electrolyte. Using the experimental thermodynamic data, to study the stability domain of SrThF6(s), the chemical potential diagram of Sr-Th-F-O system and ternary phase diagram of Sr-Th-F2 system have been calculated.

We report here on the discovery of the superconductivity of a new ternary compound LaRh2Ga2, which possesses a CaBe2Ge2-type structure. Electrical resistivity and magnetic susceptibility measurements reveal that LaRh2Ga2 undergoes a superconducting transition at 3.7 K and exhibits type-II superconductivity. The T-linear behavior of the upper critical field is likely induced by the two-gap superconducting state because of its structural features (i.e., its noncentrosymmetric structure). A transition at Tc of specific heat suggested that the LaRh2Ga2 is a weak electron-phonon-mediated superconductor. Comparison with a related superconductor demonstrates that there is an important factor other than electron-phonon coupling strength that induces higher Tc in the LaTM2Ga2 system with a noncentrosymmetric CaBe2Ge2-type structure.

International audience; The structure, the chemistry, and the magnetic properties of MnCoGe thin films elaborated by reactive diffusion were investigated. In situ X-ray diffraction (XRD) was used to study phase formation during thin film reaction. MnCo, MnGe, and CoGe binary systems were studied before investigating phase formation during Mn-Ge-Co ternary system reaction. Three pure layers of Mn, Ge, and Co were successively deposited by magnetron sputtering on SiO2 to form a 200 nm-thick Co/Ge/Mn stack, and annealed. Six phases were observed during reaction, first following the sequential phase formation observed for the binary systems at the two Mn/Ge and Ge/Co interfaces, and ending with the formation of a single ternary compound MnCoGe at 673 K. The structure and the composition of the MnCoGe films were characterized using XRD, atomic force microscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The magnetic properties of the films were studied using superconducting quantum interference device (SQUID) and ferromagnetic resonance (FMR) measurements. The obtained MnCoGe thin films are polycrystalline with the stoichiometric composition Mn:Co:Ge(1/3:1/3:1/3), and show high porosity. They are made of grains exhibiting both the Ni2In-type hexagonal structure and the TiNiSi-type orthorhombic structure.

The 600 and 800 °C isothermal sections of the Al-Sb-Cr ternary system were studied by scanning electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. No ternary compound was found in this system at either 600 or 800 °C. AlSb can equilibrate with all phases in both the 600 and 800 °C isothermal sections except Cr. Ten three-phase regions were clearly identified in the Al-Sb-Cr ternary system at 600 °C and seven three-phase regions were confirmed in the 800 °C isothermal section.

The Al–Cr–Dy system has been investigated over the whole composition by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscope and energy dispersion spectroscopy (SEM-EDS). The existence of known compounds Al8Cr4Dy and Al43Cr4Dy6 has been confirmed at 773 K. Binary compounds Al11Cr2 and Al17Dy2 do not exist in this isothermal section. The structure of the CeCr2Al20-type ternary compound Al20Cr2Dy has been determined with Rietveld refinement. This compound belongs to space group Fd 3 ¯ m and lattice parameter a = 1.44524 nm. The results shows that there are 16 single-phase regions, 31 two-phase regions and 16 three-phase regions in the studied isothermal section. The maximum solubility of Cr in AlDy2 and Al2Dy are confirmed to be 1.8 and 2.1 at. %, respectively. No significant solid solubility can be found in the other binary compounds of the Al–Cr–Dy ternary system at 773 K.

The phase equilibria of the Co-Ti-Ru ternary system at 1000, 1100, and 1200 °C were studied using the electron probe microanalyzer and x-ray diffraction. The results show that: (1) no ternary compound exists in the isothermal sections from 1000 to 1200 °C; (2) the phases of CoTi and TiRu form the continuous solid solution phase (Co,Ru)Ti; (3) the solubility of Ru in the Co3Ti phase is less than 5 at.% at isothermal sections 1000-1100 °C. These experimental results will provide useful information for the foundation for alloy design and the supplement for thermodynamic databases.

Despite the improvements seen in efficiency of GaAs cells over the years, there remains room for improvement for it to approach the theoretical single junction limit posited by Shockley and Quiesser decades ago. One of the more pursued options is the growth of quantum wells within the structure of GaAs to enhance its photon absorption below its bandgap. Multiple Quantum Wells (MQW) have been an ongoing topic of research and discussion for the scientific community with structures like InGaAs/GaAs and InGaP/GaAs quantum wells producing promising results that could potentially improve overall energy conversion. Here, we used WEIN2K, a commercial density functional theory package, to study the ternary compound Ga1-xTlxAs and determine its electronic properties. Using these results combined with experimental confirmation we extend these properties to simulate its application to form a MQW GaAs/ Ga1-xTlxAs solar cell. Ga1-xTlxAs is a tunable ternary compound, with its bandgap being strongly dependent on the concentration of Tl present. Concentrations of Tl as low as 7% can reduce the bandgap of Ga1-xTlxAs to roughly 1.30 eV from GaAs’s 1.45 eV at room temperature with as little as a 1.7% increase in lattice constant. The change in bandgap, accompanied by the relatively small change in lattice constant makes Ga1-xTlxAs a strong candidate for a MQW cell with little to no strain balancing required within the structure to minimize unwanted defects that impede charge collection within the device. Our GaAs photodiode with TlGaAs MQWs shows an expanded absorption band and improved conversion efficiency over the standard GaAs photovoltaic cell with dilute concentrations of Tl incorporated into the compound.

The phase equilibria in the Al-Ni-La system and the microstructure and mechanical properties of the alloys with varying La and Ni contents were investigated by using thermodynamic calculations (Thermo-Calc software), electron microscopy, energy dispersive spectrometer and tensile test. It is shown that the microstructure of the most promising alloys with La contents of up to 8 wt% and Ni contents of up to 5 wt% consists of Al primary crystals and ultrafine ternary eutectic (particle thickness is about 30–70 nm) which in turn consist of binary Al3Ni and Al4La compounds. However, at an excessive concentration of La and Ni, the formation of the previously undescribed Al9LaNi2 ternary compound is observed. The actual structure of the ternary diagram is proposed based on experimental data. Uniaxial tensile testing of the promising Al7La4Ni alloy in as-cast state revealed an ultimate tensile strength of about 250 ± 10 MPa, a yield strength of 200 ± 10 MPa and a ductility of 3.0 ± 0.2%.

CdSe@CdS@TiO2 microsheet array (MSA) ternary core–shell heterojunctions were prepared by successive electrodeposition of CdS and CdSe onto TiO2 microsheets using cyclic voltammetry. The photoelectrochemical performance of CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions is significantly improved. This structure not only greatly enhances the utilization efficiency of visible light but also greatly extends the spatial separation of photoinduced charge. This is because CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions have an inherent cascade energy band structure and a high-quality contact between each other at the interface. After annealing, CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions show a further improved photoelectrochemical performance because the formation of ternary compound CdS1−xSex enhances the quality of the contact interface between CdSe and CdS layers and consequently increases the transportation efficiency of photoinduced charges and injection efficiency of photoinduced electrons to the TiO2 layer. The maximum photocurrent density of 3.5 mA/cm2 was observed in the CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions after annealing at 350 °C, which is 9.46, 3.18 and 2 times higher than that observed in CdS@TiO2 MSA, CdSe@TiO2 MSA, and as-prepared CdSe@CdS@TiO2 MSA photoelectrodes, respectively.

The thermodynamic description of the ternary system B-Ti-Zr has been obtained by modelling the Gibbs energy of all individual phases using the CALPHAD (CALculation of PHAse Diagrams) approach. There is no ternary compound in this system. The individual solution phases, i.e. Liquid, (βTi, βZr), TiB, (Ti, Zr)B2 and ZrB12 have been modeled. The modeling covers the whole composition and temperature ranges. The Gibbs energy of ZrB2 in the B-Zr system was reassessed using the two-sublattice model (B, Zr)1(B, Zr)2. A set of self-consistent thermodynamic parameters for the B-Ti-Zr system was obtained by considering the phase diagram data in the ternary system. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data showed that the experimental information was satisfactorily accounted for by the present thermodynamic description. The liquidus projection and reaction scheme of the B-Ti-Zr system have also been presented.

In this paper, the TeMo5O16 ternary and MoO3-TeO2 binary compounds were prepared by using the solid-state reaction method and with MoO3-TeO2 oxide precursor solutions. The effect of pH and annealing temperature on the structure especially formation of TeMo5O16 ternary phase and optical properties of nanoparticles have been investigated. Ammonia (NH3) and nitric acid were used to adjust low and high pH, respectively. Synthesis and the formation of TeMo5O16 ternary compound were carried out at two processes: (A) chemical reduction with NaBH4 under nitrogen atmosphere and (B) annealing at temperatures T = 350 °C and 400 °C in air. These two temperatures were chosen because of the proximity to Te’s melting point. The results of X-ray diffraction showed that with increasing the annealing temperature, the MoO3-TeO2 binary composition is increased and an additional Te2O5 phase is observed. Also, with decreasing pH, the TeMo5O16 ternary phase is increased. The field emission scanning electron microscope (FE-SEM) images showed that the morphology of the nanoparticles is sphere-like, polyhedral forms, which indicates the presence of particles in different phases. The UV–Vis spectroscopy results showed that the energy gap of nanoparticles is varied in the range of 2.83–2.94 eV. The bonding structure of nano-particle was also studied by FT-IR spectroscopy.

The isothermal section at 800°C of the phase diagram of the ternary system Sc–Cu–Al was constructed in the whole concentration range using X-ray powder diffraction data. The existence of eight ternary compounds was confirmed: ScCu4.9‑6.0Al7.1‑6.0 (structure type ThMn12, Pearson symbol tI26, space group I4/mmm), Sc6Cu24.1Al11.9 (own structure type, cI176, Im-3), Sc2Cu6.25Al4.75 (own structure type, oS108, Cmmm), Sc3Cu7.5Al7.5 (Sc3Ni11Ge4, hP38, P63/mmc), ScCu2Al (MnCu2Al, cF16, Fm-3m), ScCu0.8Al0.2 (CsCl, cP2, Pm-3m), ScCu0.6Al1.4 (MgNi2, hP24, P63/mmc), and ScCuAl (MgZn2, hP12, P63/mmc), and the existence of a continuous solid solution ScCu1-xAlx (x = 0-1), based on the binary compounds ScCu and ScAl with CsCl-type structure (cP2, Pm-3m), was established. The investigation of the Ti–Cu–Al system at 800°C confirmed the existence of four ternary compounds: TiCu0.25Al2.75 (ZrAl3, tI16, I4/mmm), TiCu0.3-0.6Al2.7-2.4 (Cu3Au, cP4, Pm-3m), TiCu2-2.7Al1-0.3 (MnCu2Al, cF16, Fm-3m), and TiCu0.54-1.16All.46-0.84 (MgZn2, hP12, P63/mmc). Electrical resistivity measurements were performed for three compounds in the Sc–Cu–Al system and confirmed metal behavior in the temperature range 5-290 K.