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In this work we have investigated electronic, magnetic and transport properties of rare-earth ternary compound BaTbO3 based on density functional theory using the generalized gradient approximation. This material is found to be ground state antiferromagnetic semiconducting in nature with direct energy gap of 0.8 eV. The study of transport properties under constant relaxation time approximation (τ=10-14) and rigid band approximation using BoltzTraP code in the temperature range 300-1200 K have found large value power factor and figure of merit 124 µW cm-1K-2 and 0.78 respectively at 1200 K, and can be enhanced with p-type dpoing. Which indicates the potential candidate for good thermoelectric material.

Intermetallic compound (IMC) layers growth in the interconnections of solar modules is inevitable once the solar modules are in use. Higher temperatures (warmer climates) may accelerate the growth of these compounds, leading to faster degradation of the solar modules. In this paper, the effect of Platinum (Pt) additions on the interfacial reaction, contact resistivity and power output of solar module have been investigated. The changes in IMC morphology was studied using the scanning electron microscope (SEM) with an energy dispersive X-ray (EDX). The contact resistivities of solder joints were measured using the transfer length method. Solar modules with varying amounts of Pt additions were constructed and their power outputs under natural sunlight were compared to the reference solar module constructed with a commercial Sn-3.0Ag-0.5Cu (SAC305) solder. Experimental results showed that minute Pt additions effectively suppressed the IMC growth during isothermal aging at 150°C for up to 500 hours. This was reflected in the reduced contact resistivities ranging between 20->60% when 0.10wt.%-0.50wt.% of Pt were added to the SAC solder. In trend with the reduced resistivities, the solar modules containing Pt recorded higher power outputs and lower degradation rate under natural sunlight exposure. Pt is believed to dissolve and form an ternary compound, (Cu,Pt)6Sn5 which is less susceptible to decompose into the more detrimental Cu3Sn IMC layer, thus slowing down the overall degradation of the solar panels.

First principles calculations by using of projected augmented plane-wave method have been performed to investigate the structural, elastic and electronic properties of MgB2C2 under different pressures. The results indicate that the ternary compound of MgB2C2 remains mechanically stable under pressure ranging from 0 to 50 GPa. Elastic analysis is performed and it is found that MgB2C2 always shows obvious intrinsic brittleness under pressure, although an increasing trend of the ductility both from BH/GH and vH with increasing pressure. (100), (010) and (1-10) planes show strong anisotropy and the degree of anisotropy decreases with increasing pressure, in the meantime, it is interesting to find that the degree of anisotropy is reduced in order of planes (1-10)-(100)-(010) under the same pressure.

The search for high-temperature superconductivity has proceeded from two rather separate sources of motivation. Empirical work on binary and ternary compound superconductors and oxides (for a comprehensive review, see Ref. 1) brought the critical temperature of superconductors to 23 K in the early 1970s, a critical temperature not to be exceeded until the discovery of superconductivity in the Cu-O system in 1986 by Bednorz and Muller [2].

The ternary compound BiFeO3–BiCoO3–BaTiO3 (BFO–BCO–BT) was prepared using the solid-state reaction method. The dielectric studies display strong frequency-dependent anomaly in the vicinity of Curie temperature (TC) ≈ 350 °K and exhibit strong diffusive relaxor behavior with (γ ≈ 1.61). The dielectric measurements confirm stabilization in BFO–BT solid solution due to BCO addition. The P–E loops display strong ferroelectric behavior and frequency variation indicating major dominant domain wall movement on high dielectric constant in the BFO–BCO–BT ternary compound. The magnetic field variation in the P–E loop displays strong magnetoelectric coupling originating from interfacial polarization with maximum coupling coefficient of 115 mV/cm-Oe at field of 500 Oe. The temperature variation of P–E shows enhanced configurational entropy due to increase in activation energy, with the highest isothermal energy (ΔS) = 0.15 J/kg/K obtained for E = 15 kV/cm and T = 125 °C. These studies provide tunable ferroelectric properties of BFO–BCO–BT for exploration of promising applications such as refrigeration and magnetoelectricity.

There has been an upsurge in the discovery of topological quantum materials, where various topological insulators and semimetals have been theoretically predicted and experimentally observed. However, very few of them contain silicon, the most widely used element in the electronics industry. Recently, ternary compound $\mathrm{CaA}{\mathrm{l}}_{2}\mathrm{S}{\mathrm{i}}_{2}$ has been predicted to be a topological Dirac semimetal, hosting Lorentz-symmetry-violating quasiparticles with a strongly tilted conical band dispersion. In this work, by using high-resolution angle-resolved photoemission spectroscopy, we investigated the comprehensive electronic structure of $\mathrm{CaA}{\mathrm{l}}_{2}\mathrm{S}{\mathrm{i}}_{2}$. A pair of topological Dirac crossings is observed along the ${k}_{z}$ direction, in good agreement with the ab initio calculations, confirming the topological Dirac semimetal nature of the compound. Our study expands the topological material family on Si-containing compounds, which have great application potential in realizing low-cost, nontoxic electronic devices with topological quantum states.

First principles calculations by using of projected augmented plane-wave method have been performed to investigate the structural, elastic and electronic properties of MgB2C2 under different pressures. The results indicate that the ternary compound of MgB2C2 remains mechanically stable under pressure ranging from 0 to 50 GPa. Elastic analysis is performed and it is found that MgB2C2 always shows obvious intrinsic brittleness under pressure, although an increasing trend of the ductility both from BH/GH and vH with increasing pressure. (100), (010) and (1-10) planes show strong anisotropy and the degree of anisotropy decreases with increasing pressure, in the meantime, it is interesting to find that the degree of anisotropy is reduced in order of planes (1-10)-(100)-(010) under the same pressure.

Generalised stacking fault energy surfaces (Γ-surfaces) are calculated for Co-Al-W-based and Ni-Al-based superalloys from first-principles calculations. A Special Quasi-random Structure is employed in the calculation of the ternary compound, Co3(Al,W). Phase field simulations are used to compare dislocation cores present in Co-based and Ni-based superalloys. The higher planar fault energies of the Co-based system lead to a more constricted dislocation which can have implications on both the bowing of dislocations as well as cross-slip. Additionally, planar fault energies of various L12 compounds are compared to explain observed segregation pathways in both types of superalloy. Both the planar fault energies and the segregation pathways are discussed within the context of strengthening mechanisms in superalloys.

Solid state sciences 105, 106282 (2020). doi:10.1016/j.solidstatesciences.2020.106282, Pt(Cu$_{0.67}$Sn$_{0.33}$) has recently been found in a natural sample. In order to be able to characterize this new ternary compound, we synthesized it from the elements. Samples were characterized by X-ray powder diffraction, differential scanning calorimetry, thermal relaxation calorimetry, and scanning electron microscopy studies. Density functional theory-based model calculations complemented the experimental studies. Pt(Cu$_{0.67}$Sn$_{0.33}$) was already formed at a relatively low temperature of 773 K. Rietveld refinement of Pt(Cu$_{0.67}$Sn$_{0.33}$) has been carried out in CuAu-type or L1$_0$-type structure, space group , with Pt on 0,0,0 and disordered Cu and Sn on $\frac{1}{2},\frac{1}{2},\frac{1}{2}$ and Z = 1. The lattice parameters are = 2.823(1) Å, = 3.64(1) Å, and = 29.00(4) Å ; which are in good agreement with values obtained earlier on the natural sample and with the results of DFT calculations. The vibrational entropy for Pt(Cu$_{0.67}$Sn$_{0.33}$) is $S^{vib}_{298.15}$ = 79.9(7) J mol$^{−1}$ K$^{−1}$. The pressure dependence up to 36(2) GPa of the unit-cell volume and the lattice parameters and unit-cell volume have been obtained by synchrotron based powder diffraction using a diamond anvil cell. A fit of a 3-order Birch–Murnaghan equation of state to the Pt(Cu$_{0.67}$Sn$_{0.33}$) (p, V)-data results in a bulk modulus of B$_0$= 215(27) GPa and B´= 5(2)., Published by Elsevier, Amsterdam [u.a.]

Carbon nanotube – highly reduced graphene oxide – transition metal oxide (ZnO) nanohybrid layers were synthesized using a one-step laser technique. Commercial multiwall carbon nanotubes (MWCNTs), graphene oxide (GO) platelets and ZnO nanoparticles were used as starting materials. We discuss the influence of carbon/metal oxide ratio on the physico-chemical properties of the nanohybrid layers, geometrical characteristics, shape and dimensions of constituent nanoentities, chemical composition and chemical bonding states, optical properties, UV–visible absorption, band gap values, as well as charge transfer properties. In the followings the relation between these properties and functional characteristics, removal of water contaminants, antibiotic molecules, and charge storage performances of the ternary, MWCNTs/reduced GO/ZnO layers are presented, identifying the optimum relative concentrations of the constituting nanomaterials. The high photocatalytic efficiencies both under UV and visible light irradiations, even after several consecutive degradation cycles, were attributed to effective separation of photogenerated charge carriers by carbon nanomaterials as well as formation of oxygen deficient ZnOx−1 nanocrystals. The enhanced charge storage capacity of ternary nanohybrid electrodes is based on combined electrochemical double layer capacitance and pseudocapacitance implying redox reactions on the surface and subsurface of the layers in contact with the electrolyte. Both functional properties are strongly influenced by the relative concentrations of the nanomaterials constituting the ternary layers., The authors thank the financial support of the Executive Unit for Financing Higher Education, Research, Development and Innovation of the Romanian Ministry of Education and Scientific Research under the contract PN-III-P4-ID-PCE-2016-0550, the Spanish Ministry of Economy, Industry and Competitiveness under the projects ENE2017-89210-C2-1-R, AEI/FEDER,EU. ICMAB acknowledges financial support from the Spanish Ministry of Economy and Competitiveness, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496).

We have synthesized single crystal of layered ternary compound having composition TaIrTe4 using tellurium flux method. Herein, we report experimental study of magneto-transport properties on Weyl semimetal TaIrTe4 in the temperature regime 2.5K to 300K. TaIrTe4 show the linear magneto-resistance 4.1 % at 3.5K in a magnetic field of 6 T. The residual resistivity ration (RRR) is around 2.4. HR-TEM and SEAD patterns reveal the formation of single crystal TaIrTe4.

The increase in water pollution in recent time has generated lots of attention on photocatalysis for the remedial action of highly polluted environment from the toxic effect of dyes. Different semiconductor nanomaterials have been incorporated into carbon-based materials for photocatalytic degradation of dyes. However, most of these materials have different shortcomings that impede their efficiency. Immobilization of nanoparticles on the surface of graphene oxide is one of the routes to its utilization in the development of functional materials. Graphene possesses properties that can enhance the chemical and physical properties of nanomaterials, thus improving their application in environmental remediation. It possesses good property as an efficient adsorbent in dye degradation. Copper-based ternary compound semiconductors are alternatives to binary compound semiconductors due to their good photocatalytic performance. The combination of both materials will result in a synergy between photocatalysis and adsorption process, resulting in improved degradation efficiency of the nanocomposite.

BGaAs/GaAs epilayers and BInGaAs/GaAs quantum well (QW) have been prepared using metal-organic chemical vapor deposition under different growth conditions, and their physical and structural properties have been examined. SEM-EDS investigation showed a dependence of surface properties of the ternary compound on the growth conditions. High-resolution X-ray diffraction evidenced a tensile strain for the ternary alloys whatever the growth condition, while the quaternary QW always shows a compressive strain state. Room temperature optical absorption allowed to follow the variation of the bandgap with boron incorporation. Photoluminescence measurements confirmed the carrier-localization phenomenon and its dependence with the growth conditions. Deposition temperature and diborane (B2H6) flow rate are with particularly significant effects on the optical properties: lower diborane flow rate and high growth temperature enhance the radiative emission. Computer simulation using localized state ensemble model quantitatively relates the lattice inhomogeneity to the optical properties and suggests a way to engineer the localization phenomenon and avoid clustering effects. Electrical investigations by current-voltage, capacitance and conductance methods have been performed for the first time on selected BGaAs samples. The ideality factor of Schottky barriers has been determined, while their height and film doping level could only be approximately estimated. Such physical properties make boron-based alloys very promising for applications in multijunction solar cells.

Spark plasma sintering (SPS) was used to fabricate the Co−Hf−Mo−Ni diffusion multiple in a designed geometry to contain two Co−Hf−Mo and Co−Hf−Ni diffusion triples in one sample, which offers a high-efficiency and low-cost method for preparing this diffusion multiple. In this work, the phase equilibria of the Co−Hf−Mo system at 1373 and 1223 K were established according to the analysis of results obtained using a scanning electron microscope (SEM), X-ray diffraction (XRD), and electron probe microanalysis (EPMA) from annealed diffusion triples and equilibrated alloys. The homogeneity range of the ternary compound τ with Hf9Mo4Co structure was verified in diffusion triples, and solubilities of Mo in Co−Hf, Co in Mo−Hf, and Hf in Co−Mo binary compounds were detected at 1373 and 1223 K. The isothermal sections over the entire composition range at 1373 and 1223 K were successfully constructed. The obtained phase equilibria data provide guidance for the development of multicomponent γ/γ′ Co-based superalloys

We studied the effect of Mn on the structure and properties of Cd3−xMnxAs2 crystals with x = 0–0.24, synthesized by direct fusion of high-purity elements. Obtained X-ray diffraction patters suggest that the incorporation of Mn promotes a structural phase transition from primary α-Cd3As2 (x = 0) phase to the α''– Cd3As2 (x = 0.24) phase, while at intermediate compositions both phases can coexist. In addition, the increase of Mn content results in the decrease of lattice cell parameters, which effectively saturates for x > 0.13. Microstructural, calorimetric and magnetometry studies suggest that at high Mn content (x = 0.24) secondary MnAs phase appears. Using obtained results, we estimated the solubility limit of Mn in Cd3As2 as x~0.13, which corresponds to the formation of ternary Cd3−xMnxAs2 compound where Cd atoms are partially substituted by Mn. Formation of ternary compound was also suggested by the results for Cd3As2 + MnAs composite systems, where we also observed the presence of CdAs2 phase, which is a byproduct of corresponding reaction. Additional studies suggested that the CdAs2 phase formation in composite system can be prevented if one uses the Cd3−xMnxAs2 compound instead of pure Cd3As2 as a matrix material.

The isothermal section at 1273 K of the Co–Ni–Ti system was determined using equilibrated alloys by means of scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The experimental results indicated that eight three-phase regions and a ternary compound τ with Co3V-structure existed. Meanwhile, this system was thermodynamically modeled using the CALculation of PHAse Diagram (CALPHAD) method. The isothermal section at 1273 K measured in this work as well as the four isothermal sections at 1373, 1273, 1223 and 1173 K and the liquidus surface projection from the literatures were taken into account in the present optimization work. A set of self-consistent thermodynamic parameters of the Co–Ni–Ti system was first derived.

Herein, we synthesize dense, predominantly single-phase polycrystalline samples of the Mn2AlB2 ternary compound, using reactive hot-pressing of manganese, aluminum, and boron powder mixtures under vacuum. With a Vickers hardness of 8.7 GPa, Mn2AlB2 is relatively soft for a transition metal boride and lacked dominant cracks at the corners of the indentations. With Young’s and shear moduli of 243 GPa and 102 GPa at 300 K, respectively, it is reasonably stiff. The Poisson’s ratio is calculated to be 0.19. With compressive strengths of 1.24 ± 0.1 GPa, the samples were quite strong considering the grain size (1–15 μm). The electrical resistivity at 300 K was ∼5 μΩm and decreased linearly upon cooling. At 0.0036 K−1, the temperature coefficient of resistivity was relatively high compared to MoAlB. The average linear thermal expansion coefficient was also found to be relatively high at 18.6 × 10-6 K−1 from 298 to 1173 K. Mn2AlB2 was not thermally stable above ∼1379 K. While Mn2AlB2 was not machinable with conventional tooling, intriguingly, high-speed carbide tools bits readily penetrate the surface – with no cracking or chipping for a few millimeters – before stopping.

On the basis of all the presently determined experimental data, as well as the formerly reported isothermal sections of the Ce-Co-Sb ternary system, it was thermodynamically assessed by means of CALPHAD technique. For Ce-Co and Co-Sb binary systems, thermodynamic parameters previously obtained were considered and a re-assessment work of the Ce-Sb system is presented. In particular, the Kaptay exponential model, rather than the Redlich-Kister polynomials, is used to describe the interactions between Ce and Sb in the liquid phase of the Ce-Sb system, mainly to avoid the abnormal miscibility gap of liquid phase in the Ce-Co-Sb system at the Co rich region, and also to guarantee the consistent phase equilibria between the experimental isothermal sections and the calculated ones of the Ce-Co-Sb ternary system. The ternary compound CeCouSb2 is modeled as Ce2/9(Co%,Va)1/3Sb4/9 in order to describe the fluctuation of Co atoms in this compound. The ternary compound CeCoSb3 is regarded as a stoichiometric phase. The previously optimized thermodynamic parameters of other phases were adopted in the present work. A set of self-consistent thermodynamic parameters were finally obtained and fit well with the experimental results from various literatures, which will contribute to the further development of the CoSb3-based thermoelectric materials, especially from the perspective of the couping of electron-phonon interactions.

Series of ion conducting system (KI)4 – x‒(CuI)x‒PbI2, x = 0.0‒0.4, have been prepared by solid state reaction method and studied by powder X-ray diffraction, DTA techniques and conductivity measurements. Room temperature XRD reveals the presence of the orthorhombic KPbI3 as the major component in the sample. The X-ray diffraction analysis also confirms the presence of both KI and CuPbI3 in the samples. DTA of x = 0.0 composition shows an endothermic peak at 349°C attributed to the melting of the compound. AC impedance spectroscopy revealed that the contribution of grain is strong over the grain boundary. The addition of CuI content results in the increase of electrical conductivity of the samples. The maximum ionic conductivity σ = 6.33 × 10–1 S cm–1 was shown by x = 0.3 composition at 633 K with lowest activation energy of ~0.11eV in the temperature range of 298‒633 K.

Dissimilar lap joining of magnesium alloy to titanium alloy was performed using Ni coating by laser welding-brazing process. The influence of different Ni-coating thicknesses on microstructure and mechanical properties were investigated. In laser irradiation region, Ti3Al phase formed at fusion zone/Ti interface. In middle region, Ti3Al phase still existed at fusion zone/Ti interface, while Mg-Al-Ni ternary IMC generated at fusion zone. In weld toe region, Ti-Ni binary IMC were observed at the interface of fusion zone/Ti. The particles of Mg-Al-Ni ternary compound grew bigger and thickness of Ti-Ni compound layer increased with the increase of Ni-coating thickness. TiNi IMC transformed into (TiNi + Ti2Ni) mixtures when the Ni-coating thickness exceeded 5.8 μm. Interfacial microstructure evolution was clarified according to thermodynamic calculation results of formation enthalpy and chemical potential. The fracture load first increased and then decreased slightly with increasing coating thickness, the maximum fracture load (2430 N/cm) represented 90% joint efficiency in relation to the Mg base metal. The fracture mode changed from interfacial failure into fusion zone fracture when the Ni-coating thickness was greater than 4.0 μm. The interfacial bonding were relatively low, while the performance of fusion zone fracture was relatively high. Further increase of coating thickness has little effect on the performance deterioration. The bonding mechanism of Mg to Ni-coated Ti were illuminated.

The phase equilibria of the Ho-Zr-Si ternary system were experimentally determined at 973 K (700 °C) in the entire concentration range by using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS), and differential scanning calorimetry (DSC). The results show that there are 13 single-phase regions, 23 two-phase regions, and 11 three-phase regions in the investigated isothermal section, and no ternary compound is found. The composition ranges of all phases are extremely small. Among these, there are ten extensions of the binary compounds, i.e., ZrSi2, α-ZrSi, α-Zr5Si4, Zr3Si2, Zr2Si, β-HoSi2-a, α-HoSi2-b, HoSi, Ho5Si4, and Ho5Si3, in the ternary system. They are Zr1–xHoxSi2 (x ≤ 0.084), α-Zr1–xHoxSi (x ≤ 0.156), α-Zr5–xHoxSi4 (x ≤ 0.945), Zr3–xHoxSi2 (x ≤ 0.550), Zr2–xHoxSi (x ≤ 0.180), β-Ho1–xZrxSi2–a (x ≤ 0.124), α-Ho1–xZrxSi2–b (x ≤ 0.147), Ho1–xZrxSi (x ≤ 0.220), Ho5–xZrxSi4 (x ≤ 1.368), and Ho5–xZrxSi3 (x ≤ 0.592), respectively. In the present work, the phase transformation temperatures of β-HoSi2-b → α-HoSi2–b and Ho3Si4 → β-HoSi2–b + HoSi are determined to be 979.7 K (706.7 °C) and 1479.3 K (1206.3 °C), respectively, by analyzing the DSC results.

The isothermal section of the Zr-Si-Y ternary system at 900 °C has been investigated using x-ray power diffraction, Scanning electron microscopy coupled with energy-/wave-dispersive x-ray spectroscopy. Nine three-phase equilibrium regions were determined experimentally. No ternary compound was observed in the present work. The 9 binary compounds Zr2Si, Zr3Si2, Zr5Si4, ZrSi, ZrSi2, Y5Si3, Y5Si4, YSi and Y3Si5 were confirmed to exist in the Zr-Si-Y ternary system at 900 °C. The solubility of the third component in the binary compound was determined experimentally.

Current commercial thin film photovoltaic technologies rely on the use of scarce and/or toxic elements, motivating the necessity to explore new technologies free of critical raw materials. In this work we report the first Cu3BiS3 based solar cells with proved photovoltaic activity using standard substrate configuration. The absorbers were synthesized using a sequential process based on metallic stacks evaporation followed by a reactive annealing under S atmosphere. With the optimization of composition (Cu/3: Bi ratio), metallic stack order, annealing parameters and Na doping, we achieve a record conversion efficiency of 0.11%. Combining several characterizations techniques, we show that at this stage of the technology development, issues like composition, secondary phases and morphology cannot explain the low efficiencies obtained with this material. Through a deeper characterization of the devices, we found that most probably, this is related to either, a high doping of the absorber, and/or poor transport charge properties. Understanding and solving these issues, can further help to improve the efficiency of Cu3BiS3 based devices towards more competitive conversion efficiencies.

In order to progress in the development of Lead-cooled Fast Reactors, from the safety point of view it is essential to understand the chemical compatibility between liquid lead and uranium oxide. In the present work, entropy and heat capacity of Pb3U11O36, a possible ternary compound coming from fuel-coolant chemical interaction, were determined for the first time. Entropy at 298.15 K was obtained from low temperature heat capacity measurements using the Physical Property Measurement System (PPMS) in the temperature range 2–300 K, while the high temperature heat capacity has been measured by a drop calorimeter from 373 K to 1200 K. The experimental thermodynamic properties were compared with the values computed by means of DFT-GGA simulations, obtaining a very good agreement.

The 150 °C isothermal section of Li–Si–Mn ternary system has been investigated experimentally and extrapolated using the optimized thermodynamic parameters from the constitutive binary systems. About 30 ternary alloys were examined by means of scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD). Nine three-phase regions have been detected, i.e. Li12Si7+Mn11Si19+(Si), Li12Si7+MnSi+Mn11Si19, Li7Si3+Mn5Si3+MnSi, Li7Si3+Mn5Si3+Li13Si4, Li22Si5+Mn5Si3+Mn3Si, Li22Si5+Mn3Si+Mn9Si2, Li22Si5+Mn9Si2+Mn6Si, Li22Si5+Mn6Si+(Li) and (Li)+(αMn)+Mn6Si. No ternary compound has been observed for this ternary system. Furthermore, thermodynamic assessment of Li–Mn binary system has been carried out with the CALPHAD approach on the basis of the experimental data. And the thermodynamic parameters of the Si–Mn system from literature have been revised. The compounds MnSi1.75-x and MnSi were simply modeled by the sublattice models as (Mn)11(Si)19 and (Mn)1(Si)1 respectively to adapt to the multicomponent system. Thermodynamic extrapolation of the Li–Si–Mn ternary system showed good agreement with the experimental phase relationships.

A ternary compound of magnesium diniobate (MgNb2O6) was prepared by solid–state reactions in order to understand the role of transition metal oxides as a promoter/catalyst for hydrogen storage in Mg/MgH2 systems. MgNb2O6 was prepared in almost pure form in oxidizing conditions by annealing a stoichiometric mixture of MgO and Nb2O5. The effect of calcination temperatures on phase formation, reaction kinetics, and heat of reaction of the solid–state product was investigated by ex situ, in situ X-ray diffraction (XRD), and differential scanning calorimetry (DSC). Hydrogen sorption properties of the compound were investigated by mass spectrometer. The crystallographic parameters of binary and ternary Mg–Nb–O phases were extracted by Rietveld method. During solid–state synthesis, the formation of MgNb2O6 provides single-step reaction between precursor materials proved by in situ experiment and the heat of formation as well as driving force was calculated from calorimetric analysis.

We report here a comprehensive investigations of the band structure, magnetic properties, electrical transport, and specific-heat for ternary compound Ce5RuGe2 that crystallize in orthorhombic Y2HfS5-type structure. The results show a complex magnetic structure with the field-induced metamagnetic transitions in coexistence with spin-glass-like phase, displayed in the magnetic H − T phase diagram. Simultaneously, a combined experimental and theoretical study based on x-ray photoelectron spectroscopy (XPS) data together with ab initio band structure calculations indicate a mixed valence of Ce due to strong hybridization between Ce 4 f states and conduction band. The obtained magnetic ground state of Ce5RuGe2, resulting from localized f-electron states and accompanying strong hybridization effect leading to valence instability of cerium ions are rarely observed for Ce-based intermetallic compounds.

The 600 and 800 °C isothermal the sections of Al-Si-La ternary system between 0 and 50 at.% La have been established via a combination of electron microprobe analysis and X-ray powder diffraction. A total of three ternary compounds were confirmed in this work and temporally designated τ1, τ2 and τ3. The three ternary compounds (τ1-τ3) were found at 600 °C. The ternary phase τ1 spans 43.3 at.% to 61.5 at.% Al, 5.0 at.% to 21.3 at.% Si, and 33.5 at.% to 35.5 at.% La. One ternary compound, τ1, was identified at 800 °C. The τ1 phase spans 43.6 at.% to 62.6 at.% Al, 4.1 at.% to 22.5 at.% Si, and 33.1 at.% to 35.2 at.% La. The solubility of Al in LaSi2-α2 is 39.9 at.% and 41.3 at.% at 600 and 800 °C, respectively. The solubility of Si in Al2La at both 600 and 800 °C is extremely small.

The crystal structure of the novel Al-rich intermetallic phase Ce4Pt9Al13 was determined from single-crystal X-ray diffraction data and confirmed by powder X-ray diffraction. The compound crystallizes with its own structure type, which is a “site exchange” variant of the Ho4Ir13Ge9-type (Pearson symbol oP52, space group Pmmn, No. 59, Z = 2, lattice parameters: a = 4.1826(1) A, b = 11.4424(3) A, c = 19.8475(5) A, V = 949.88(7) A3). The magnetic properties of Ce4Pt9Al13 were determined in the temperature range 1.72–400 K. Down to the lowest temperatures studied, the compound shows a Curie-Weiss paramagnetic behavior with strong crystalline electric field contribution observed below about 200 K. The electrical conductivity in Ce4Pt9Al13 has metallic character, and at low temperatures it is governed by an interplay of strong crystal field and Kondo interactions.

The microstructure of the Er-Fe-V ternary system at 773 K was investigated by means of x-ray diffraction analysis and scanning electron microscopy. The isothermal section at 773 K was obtained, consisting of 9 single-phase regions, 15 two-phase regions, and 8 three-phase regions. The homogeneity range of the ternary compound ErFe12−xVx was determined to be x = 1.1 to 2.6. The maximum solid solubility of V in Fe, ErFe2, and Er2Fe17 was found to be about 13.0 at.%, 5.3 at.%, and 2.5 at.%, respectively. The maximum solid solubility of Fe in V was found to be about 25 at.%. Regarding the microwave absorbing properties of V-doped Er2Fe17 alloy, the absorption peak of the Er2Fe17−xVx alloys moved toward the low frequency region while the minimal reflection loss decreased upon V addition, with absorption frequency bandwidth (R

Phosphate compound with mixed cations, NaBaPO4 can be a new candidate of microwave dielectric ceramics with the basis of the systematically investigations of the ternary compound series of AMPO4 (A = Li, Na, K; M = Ca, Sr, Ba). Ceramics with single phase of NaBaPO4 can be obtained under our optimized experimental sintering conditions for this compounds above, whereas its microstructures and microwave dielectric properties are strongly influenced by the sintering temperatures and holding times. Relatively dense microstructures can be obtained under the sintering conditions of 910 °C/0.5 h, with unique combination of microwave dielectric properties as e = 8.279, Q × f = 10237 GHz (11.4 GHz) and τf = + 19.07 ppm/°C, and fast sintering characteristics (0.25 – 0.5 h) are the inherent properties of such phosphate compound.

A new ternary compound Cu3ZnSb was synthesized by high temperature solid state synthesis and characterized by single crystal X-ray diffraction and energy dispersive X-ray analysis. The ternary Cu3ZnSb crystallizes in the tetragonal crystal system with the space group P4/nmm (129), and its unit cell contains 10 atoms which are distributed over 4 independent crystallographic positions. The structure is built up with [Cu3Sb] slabs that correspond to the unit cells of Cu2Sb and planar 44 nets of Zn atoms. The planar nets of Zn atoms are interspersed between two adjacent [Cu3Sb] slabs. The structure can be viewed as alternating units of Cu2Sb and CsCl type β′-brass (CuZn) structures in the [001]. An unusual atomic ordering of two neighboring transition metals Cu and Zn is observed and is confirmed by first principle calculations. The atomic ordering of Cu and Zn is retained from binary β′-brass structure (CuZn) to ternary Cu3ZnSb. Total energy calculations confirmed the experimental model of Cu/Zn ordering to ...

The elastic and ultrasonic properties of the hexagonal intermetallic CeCuGe ternary compound have been evaluated along unique axis at room temperature. Higher order elastic constants have been calculated for CeCuGe compound using Lennard-Jones interaction potential model. The ultrasonic velocity, Debye average velocity, thermal relaxation time and acoustic coupling constant are evaluated along unique axis of the crystal and the temperature dependent ultrasonic velocities are evaluated along different angles with unique axis of the crystal. Finally temperature dependent ultrasonic attenuation is evaluated to extract important information about the material.

The 600 °C and 450 °C isothermal sections of the Co-Cu-Zn ternary system have been investigated experimentally by means of scanning electron microscopy coupled with energy dispersive x-ray spectroscopy, and x-ray diffraction. Five three-phase regions were confirmed in the 600 °C isothermal section and six three-phase regions existed in the system at 450 °C. The γ-Co5Zn21 and Γ-Cu5Zn8 phases formed a continuous solid solution, which is designated as the γ/Γ phase. No ternary compound was found in the present work. The solubility of Co in δ and β is up to 1.8 and 8.8 at% respectively, and the maximum solubility of Cu in γ1 and β1 is 14.7 and 7.9 at% respectively at 600 °C. The maximum solubility of Co in e and β ´ is 8.5 and 6.7 at% respectively, and the solubility of Cu in γ2, γ1 and β1 is up to 12.9, 14.4 and 11.2 at% respectively at 450 °C.

Polycrystalline Pr3Ir was synthesized by arc melting. Its cementite-type crystal structure (Pnma) was confirmed by powder X-ray diffraction and estimated lattice parameters are in agreement with literature. Physical properties were measured by means of the ac and dc magnetic susceptibility, electrical resistivity and heat capacity. Our results indicate spin-glass behavior in Pr3Ir with a freezing temperature Tf = 6.58 K and activation energy Ea = 2.17 kBTf. Above Tf, the dc magnetic susceptibility of Pr3Ir follows a modified Curie-Weiss dependence with a paramagnetic Curie temperature θP = 3.4 K and an effective magnetic moment μeff = 3.72 (1) μB/Pr that is somewhat larger than expected for Pr+3 (μeff = 3.5 μB/Pr). Resistivity measurement shows that Pr3Ir is a poor metal with a residual resistivity ratio about 1.6. The spin-glass scenario in Pr3Ir likely originates from the dynamic fluctuations of the magnetic interactions, as it was proposed for stoichiometric, well ordered PrAu2Si2 Pr-based ternary compound.

A series of La–Ti–Zn alloys was designed to investigate the 600 and 450 °C isothermal sections of the La–Ti–Zn system based on examination by scanning electron microscope (SEM) equipped with energy dispersive X-ray spectrometer (EDS) and X-ray powder diffraction (XRD). No ternary compound was found in the system. Nine three-phase regions were identified at both the 600 and 450 °C sections. Five Ti–Zn intermetallic compounds, TiZn16, Ti3Zn22, TiZn3, TiZn and Ti2Zn were observed in the present work. It was found that TiZn3 may not be a strictly stoichiometric compound. La does not dissolve in any of Ti–Zn binary compounds and the solubility of Ti in La-Zn binary compounds was ≤ 0.3 at%. The TiZn3 phase can equilibrate with LaZn13, LaZn11, La2Zn17, and La3Zn22, while TiZn can achieve equilibrium with La3Zn22, LaZn5, LaZn4, and LaZn2.

The main environmental problems associated with water body pollution are typically those caused by the discharge of untreated effluents released by various industries. Wastewater from the textile dye industry is itself a large contributor and contains a huge number of complex components, a wide spectrum of organic pollutants with high concentration of biochemical oxygen demand (BOD)/chemical oxygen demand (COD) and other toxic elements. One of several potential techniques to degrade such reactive dyes before being discharged to water bodies is photocatalysis, and bismuth-based photocatalysts are rapidly gaining popularity in this direction. Bismuth oxyhalides, BiOX (X=Cl, Br, I, F), as a group of ternary compound semiconductors (V-VI-VII), have been explored extensively for their photocatalytic activity due to their unique crystal lattice with special layered structure in pure as well as modified form. With suitable band gap and band edge positions, which are a required condition for efficient water breakup and high photon absorption, BiOCl scores over other oxyhalides. Photocatalytic activity depends on many factors such as synthesis method, morphology, size, illumination type, dye choice among others. This paper gives a critical review on bismuth oxyhalides as a family on various aspects of modifications such as doping (with unique and interesting metals as well), morphology and synthesis parameters, polymer and carbon assisted composites in order to further enhance the photocatalytic efficiency in UV/visible region of solar spectrum.

The interaction of components in the Dy-Sm-Ge system at 873 K was investigated by means of x-ray phase and structural analyses, microstructural analysis and energy dispersive x-ray spectroscopy. The existence of the continuous solid solutions between the isostructural binary germanides of the Dy1−xSmxGe (CrB-type), Dy5-xSmxGe4 (Sm5Ge4-type) and Dy5-xSmxGe3 (Mn5Si3-type) were established. The limited solid solutions based on the binary germanides of the SmGe2 (α-ThSi2-type), DyGe2 (TbGe2-type) and Dy11Ge10 (Ho11Ge10-type) are formed. The solubility of Dy in SmGe2 is 15 at.%, Sm in DyGe2 and Dy11Ge10 − 10 at.%, Sm. Two ternary SmxDy1−xGe1.5 (x = 0.15-0.50) and Sm2Dy2Ge7 compounds were found. SmxDy1−xGe1.5 crystallizes in AlB2 structure type. The crystal structure of the new ternary compound of the Sm2Dy2Ge7 (ordered superstructure to Nd4Ge7-type, Pearson symbol oS44, space group C2221, a = 0.5942(1), b = 1.3823(4), c = 1.1801(3) nm, V = 0.9694 nm3) was investigated by means of x-ray single crystal diffraction. The germanium atoms form 3D anionic network the existence of which was confirmed by electronic structure calculations.

In this work, we present a novel small molecule based on dithienylthienothiadiazole units (named SM1) acting as an efficient component in ternary blend organic solar cells to modify the hole extraction at the interface. Our findings show that the SM1 suppresses the surface recombination and enhances the open-circuit voltage ( V

So far, the relevant phase equilibrium relations and the type of equilibrium phase fields in the CaO-SiO 2 -La 2 O 3 basic slag system phase diagram are still unknown, which restricts the smelting process and application in materials of rare earth elements. In the current work, phase equilibrium relations within specific region of CaO-SiO 2 -La 2 O 3 system at 1673–1473 K were studied experimentally by using the thermodynamic equilibrium experiment followed by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). According to the experimental results, the existence of ternary compound CaO·3SiO 2 ·2La 2 O 3 was determined, it is confirmed to be a solution solid phase. The sub-solidus phase relations between different solid phases were also determined. Finally, the isothermal sections of CaO-SiO 2 -La 2 O 3 system within specific region at 1673 K, 1573 K and 1473 K were obtained, respectively. The experimental results can not only enrich the phase diagram information of silicate system, but also have practical significance for the application of rare earth in materials.

Corundum abrasives with plate-like grains were fabricated by a two-step sintering technique using the solution-based process with the addition of the ternary compound additive Na 3 AlF 6 -CaO-SiO 2 . The two-step sintering method showed obvious advantages over conventional sintering methods in promoting sample densification, suppressing grain growth, and homogenizing the microstructure of the corundum abrasives. The sample doped with 2.5 wt% Na 3 AlF 6 and 4 wt% CaO + SiO 2 in the molar ratio of 1:1 possessed a relative density of 99.3%, average grain size of 0.54 µm, and single-particle compressive strength of 49 N. The introduction of seeds reduced the temperature of θ- to α-Al 2 O 3 phase transformation. The relationship between the microstructure and the mechanical properties of the abrasives was also discussed.

Al3Ti-based alloys attract exceptional attention due to their high specific mechanical properties. However, their application is still insufficient due to their low ductility and fracture toughness. Several approaches were previously proposed to address these problems. The first one is stabilization of the cubic modification of titanium trialuminide by alloying. Another approach consists in fabricating metal-intermetallic laminated composites (MIL). In this study, we combined both methods to synthesize the first MIL composite with cubic Al3Ti interlayers. Copper additions were used to stabilize the cubic modification of Al3Ti and produce a novel Ti-Al5CuTi2 MIL composite. First mechanical characterization by indentation tests showed that the binary Al3Ti intermetallic tended to crack at a load of 0.2 kg while the fracture was not observed in the Al5CuTi2 layers at least at a load of 1 kg. These results are an indirect evidence of a higher ductility and fracture toughness of the composite with cubic Al3Ti compared to tetragonal one. The sequence of the phase transformations in the Al-Ti-Cu system was studied using in situ synchrotron X-ray radiation diffraction. The formation of Al5CuTi2 occurred via several intermediate stages including eutectic melting of Al and Cu and the formation of binary AlCu and Al3Ti compounds. Keywords: Sintering, Titanium aluminide, Phase transformation, Synchrotron diffraction, Fracture toughness, Ternary compound

Cation exchange mediated synthesis of nanoheterostructures (NHSs), core–shell structure or segmented nanostructures are gaining high interest in nanoscience research as the process gives a wide win...

The 650 and 750 °C isothermal sections of the Cr-Sb-Fe ternary system were determined by means of scanning electron microscopy, energy dispersive spectroscopy and x-ray diffraction. More than 40 alloys were prepared by a powder metallurgy method. Two continuous solid solution phases (Fe, Cr)Sb and (Fe, Cr)Sb2 were clearly identified. Two three-phase regions have been confirmed in the Cr-Sb-Fe ternary system at 650 and 750 °C isothermal sections. No ternary compound was found in this system.

The liquidus surface projection and isothermal section at 1373 K of the Co–Ni–Ti system have been established by using the methods of scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (PXRD), and differential thermal analysis (DTA). 9 primary solidification regions and 6 ternary invariant reactions were deduced in the liquidus surface projection. 7 three-phase regions and 16 two-phase regions were derived in the isothermal section at 1373 K. Besides, the PXRD results indicated that the ternary compound τ with Co3V-structure existed in both liquidus surface projection and isothermal section at 1373 K. The ternary compound τ formed the extended primary field in the centre of the liquidus surface projection and its homogeneity ranges of Co in the isothermal section were measured to be from 34 to 51 at%. The present experimental results could be used as guidance to practical applications and input to future thermodynamic assessments.

Insight into the phase equilibria, intermetallic compounds, solid solution and thermodynamic properties of the system of Zr, Si and rare earth elements is of academic interest for development of key structural materials in many fields. In this work, the solid state phase equilibria of the Si-Y-Zr ternary system at 1173 K were experimentally investigated by using x-ray powder diffraction and backscattered electron with energy dispersive x-ray analysis. The existence of 10 binary compounds namely, SiZr2, α-Si4Zr5, Si2Zr3, Si2Zr, α-SiZr, α-Si2Y, β-Si5Y3, SiY, Si4Y5 and Si3Y5, have been confirmed in this system at 1173 K, respectively. No binary compound was found in the Y-Zr binary system, and no ternary compound was found in current ternary system. The solid solubility of Y in the phases SiZr2, α-Si4Zr5, Si2Zr3, Si2Zr, α-SiZr, and Zr in α-Si2Y, β-Si5Y3, SiY, Si4Y5 and Si3Y5 was determined at 1173 K.

The 600 °C isothermal section of the Zn-Al-La ternary system was experimentally determined using scanning electron microscopy/energy dispersive spectroscopy, X-ray diffraction and equilibrated alloy method. The results indicate that nine three-phase regions have been identified in the Zn-Al-La ternary system at 600 °C. No new ternary compound was found in the system. La-Zn and La-Al compounds can dissolve a certain amount of Al and Zn, respectively. The solubility of Al in LaZn, LaZn5 and La3Zn22 phases is 18.6, 2.6 and 9.0 at.%, respectively, and the solubility of Al in La2Zn17 and LaZn11 phases is 17.1 and 6.3 at.%, respectively. The solubility of Zn in Al4La5, AlLa, Al2La and Al3La phases is 7.8, 7.8, 25.3 and 15.2 at.%, respectively. The ternary compound Zn2Al2La has a larger composition range, and its chemical composition can be roughly expressed as La (ZnxAl1−x)4 (0.2875 ≤ x ≤ 0.6875).