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The paper presents the results of the study of the phase composition of hypereutectic silumin Al – 16.0 at. % Si – 0.2 at. % Fe. A comparative analysis of the phase composition of samples obtained at an average melt cooling rate of 102 K/s and at an ultra-high melt cooling rate of 105 K /s was carried out. At an average rate, the samples solidified in a graphite mold, and the ultra-high melt cooling rate was provided during the production of foils by the method of ultrafast quenching from the melt. It was established by X-ray diffraction and micro X-ray spectral analysis that the rapidly solidified foils consist of an aluminum-based solid solution supersaturated by silicon, dispersed silicon particles and the AlFeSi2 ternary compound phase. Comparative analysis of the results of X-ray diffraction and X-ray spectral studies of samples obtained at different melt cooling rates indicate that, during rapid solidification, the aluminum-based supersaturated solid solution contains up to 2 at. % Si.

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%.

Tb-Si intermetallics have been recognized as interesting magnetic and electrical materials. The addition of Cr can modify the property and broaden the application of Tb-Si intermetallic compounds. Understanding phase relations, phase stability and microstructural changes of relative systems are essential for tuning and improving performance of this type of materials. In this work, phase relationships in the Tb-Si-Cr ternary system have been studied based on phase and microstructure identification of key equilibrated alloys. Isothermal sections of this system at 1273 K and 1073 K were experimentally constructed by means of electron probe microanalysis, X-ray diffraction, and differential thermal analysis. As one of results, the ternary compound TbSi2Cr2 was confirmed to exist at both 1273 K and 1073 K. In addition, remarkable solubilities of the third element were detected in some binary compounds. The solubility of Cr in Tb2Si3-δ and TbSi at 1273 K are about 4.0 and 9.1 at%, respectively. The solubility of Cr in Tb5Si3 increases from 3.0 at% at 1273 K to 6.2 at% at 1073 K. Besides, the compound Tb2Si3-δ were determined to be stable ranging from 1098 ± 25 K to 1513 ± 10 K, based on the analysis of microstructure. Moreover, the annealing temperature dependence of micro-hardness for Tb2Si3-δ intermetallic phase was investigated by nano-indentation.

The phase equilibria at 1473, 1373 and 1273 K in the Fe–Ta–Ti system were investigated by means of Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometer (EDS) and X-ray Diffraction (XRD). The experimental results indicated that Fe2Ta and Fe2Ti formed the continuous solid solution phase Fe2(Ta,Ti). No ternary compound was found in this system. The temperature of invariant reaction liquid + Fe7Ta6 → FeTi + bcc(Ta,Ti) was measured as 1431 K by Differential Thermal Analysis (DTA). Based on the experimental results in the present work, the Fe–Ta–Ti system was optimized using CALPHAD technique. A set of self-consistent thermodynamic parameters for the Fe–Ta–Ti system was obtained, and the experimental isothermal sections at 1473, 1373 and 1273 K were reproduced well.

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 γ/γ′ two-phase Co–Al–V-base superalloys are investigated in detail, including their phase equilibria, alloying effects, and alloy design. The experimental proof of the existence of a ternary compound with an L12-ordered γ′-Co3(Al, V) phase is provided in this study, and the γ/γ′ two-phase Co–5Al–14V (at.%) alloy is designed. The γ′-Co3(Al,V) phase is proved to be thermodynamically stable at 900 °C, and a wide γ/γ′ two-phase composition region in the Co–Al–V ternary phase diagram at 900 °C is identified. The performed investigation of Co–5Al–14V-2X (X: Ti, Cr, Nb, Mo, Ta, and W) and Co-xNi-8Al–12V (x = 10, 20, and 30) quaternary alloys revealed that Ti, Nb, Mo, Ta, W, and Ni tend to concentrate in the γ′ phase, whereas Cr tends to partition to the γ matrix. Besides, the γ/γ′ two-phase Co–30Ni–10Al–5V–4Ta–2Ti (30Ni4Ta2Ti) alloy is designed. The 30Ni4Ta2Ti alloy exhibits a very high γ′ solvus temperature (namely, 1242 ± 3 °C) combined with a low density (8.46 ± 0.08 g cm−3), which characteristics are comparable with those of the Mar-M-247 Ni-base superalloy. Moreover, the nominal and the specific yield strength values of the obtained 30Ni4Ta2Ti alloy within the temperature range from 600 to 900 °C are also close to those of the Mar-M-247 superalloy.

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.

Complex chalcogenide compound are widely used as working elements for semiconductor optical technology, thermal generation, solar power. Special attention is paid to compounds of the M2P2Se6 type (M – Ag, Cu) which due to its layer crystal structure possess promising ferroelectric, thermoelectric and electro-optical properties. Heterovalent substitutions of cations 2М2+ ® 4M1+ in the composition of M2P2Se6 type compounds must leads to deformation of the crystal structure, changing in the value of the dipole moment and, accordingly, to change the electro-physical properties. The Tl2Se–In2Se3–“P2Se4” system characterized by the formation of intermediate complex compounds which melts congruently TlInSe2 (1023 К), Tl4P2Se6 (758 К), TlInP2Se6 (875 К) and TlIn5Se8 (melts incongruently L+In2Se3«TlIn5Se8 at 1029 К), In4(P2Se6)3 (formed by syntactic reaction at 880 К). Triangulation of the Tl2Se–In2Se3–“P2Se4” system was shown that then divided on secondary quasiternary systems, one of them is Tl2Se–TlInSe2–Tl4P2Se6. Phase equilibria in the Tl2Se – TlInSe2 – Tl4P2Se6 quasiternary system were studied using classical methods of physicochemical analysis DTA (chromel-alumel thermocouple, with an accuracy of ±5 K), XRD (DRON-3-13 diffractometer, Cu Ka radiation, Ni filter, Guinier Huber G670 diffractometer, CuKα1 radiation), MSA (metallographic microscope Lomo Metam R1) in combination with the simplex method of mathematical modeling of phase equilibria in multi-component systems. Crystal structure calculation was carried out with program WinCSD. Investigation of physical-chemical interaction allowed to constructed perspective view of phase state diagram and liquidus surface projection of the Tl2Se–TlInSe2–Tl4P2Se6 ternary system. In the ternary system formed the boundary solid solution: a- on the basis of Tl2Se, b- on the basis of TlInSe2, g-, d-, e- on the basis of ltm-, mtm- and htm-Tl4P2Se6 (ltm, mtm, htm – low, middle and high temperature modification, respectively). The liquidus of the ternary system consists of primary crystallization areas: Tl2Se-е1-Е1-е2-Tl2Se (a phase), TlInSe2-е3-U2-U1-E1-TlInSe2 (b phase), m1-U1-E1-e2-m1 (g phase), m2-U2-U1-m1-m2 (d phase) and Tl4P2Se6-e5-U2-m2-Tl4P2Se6 (ε phase). The Tl2Se–TlInSe2–Tl4P2Se6 quasiternary system is characterized by the processes: monovariant eutectic L«htmTl4P2Se6+TlInSe2 (e5-U2, 776-693 К), monovariant eutectic L«Tl2Se+TlInSe2 (e1-Е1, 614-539 К), monovariant eutectic L«Tl2Sе+ltmTl4P2Se6 (e2-Е1, 610-539 К); monovariant peritectic L+mtmTl4P2Se6«ltmTl4P2Se6 (m1-U1, 640-620 К); monovariant peritectic L+htmTl4P2Se6« mtmTl4P2Se6 (m2-U2, 747-693 К); monovariant peritectic L+mtmTl4P2Se6«TlInSe2 (U2-U1, 693-620 К); monovariant peritectic L+ltmTl4P2Se6«TlInSe2 (U1-E1, 620-539 К). Lines of the monovariant equilibria are crossed in three point: U2 – invariant peritectic process L+htmTl4P2Se6«TlInSe2+mtmTl4P2Se6 (12 mol.% Tl2Se, 20 mol.% TlInSe2, 68 mol.% Tl4P2Se6, 693 К), U1 – invariant peritectic process L+mtmTl4P2Se6«TlInSe2+ltmTl4P2Se6 (38 mol.% Tl2Se, 9 mol.% TlInSe2, 53 mol.% Tl4P2Se6, 620 К), E1 – invariant eutectic process L « Tl2Se+TlInSe2+ltmTl4P2Se6 (47 mol.% Tl2Se, 7 mol.% TlInSe2, 46 mol.% Tl4P2Se6, 539 К). New complex compounds were not observed in the ternary system. Limited solid solutions on the basis of TlInSe2, Tl4P2Se6 initial compounds are not up to 5–8 mol%. Crystal-structure studies of Tl2Se, TlInSe2 and Tl4P2Se6 complex chalcogenides were carried out by a powder method, refinement of the structural parameters – by the Rietveld method. The lattice parameters are: Tl2Se – Р4/n, а=8,540; с=12,380 Å, TlInSe2 – I4/mcm, a=8.064, c=6.833 Å, Tl4P2Se6 – P121/c1, a=12.239, b=9.055, c=12.328 Å, b=98.83. Crystal-chemical analysis of the compounds showed that they are characterized by a mixed ion-covalent type of chemical bond. During the transition from the binary Tl2Se to TlInSe2 ternary compound the covalent component of the In–Se bond is enhanced, the opposite change is observed for Tl4P2Se6, an increase in the ion component of the Tl–Se bond. The study of the mechanisms of formation of solid solutions showed that with the reciprocal solubility of the TlInSe2, Tl4P2Se6 ternary compounds characterized by the formation of substitution structure, the dissolution of Tl2Se in ternary selenides follows the substitution and subtraction mechanism.

Actinide nitrides possessing the advantages of high burn-up, superior thermophysical properties and easy reprocessing in nitric acid, are currently considered as promising fuels for advanced nuclear reactors. In this work, a systemic study on the stability, mechanical and thermodynamic properties of (Pu, Zr)N was conducted employing the first-principles density functional theory approaches. We found that the ternary compound (Pu, Zr)N tends to exist in the form of single cubic NaCl-type solid solution, confirmed by incorporation and solution energies of Zr in PuN crystals. The calculated elastic constants of the (Pu, Zr)N crystals satisfy the stability criteria of tetragonal structures, proving their mechanical stability. It is revealed that the elastic constants and mechanical properties such as mechanic moduli and Poisson's ratio monotonically change with the concentration of Zr in (Pu, Zr)N crystals. Additionally, the specific heat also changes monotonically with the concentration of Zr derived from phonon-dispersion spectrums. The obtained results can shed light on the understanding of plutonium nitride materials in the nuclear energy cycles.

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.

The phase equilibria in the ternary systems {Ce, Gd}–{Ti, Zr}–Sb were investigated by means of X-ray powder diffraction and energy-dispersive X-ray spectroscopy. The isothermal sections of the phase diagrams at 600°C were constructed. The formation of three ternary compounds (Ce2Ti7Sb12, Ce3TiSb5, and Gd2Ti11Sb14) was confirmed in the {Ce, Gd}–Ti–Sb systems and no more ternaries were found. The investigation of the {Ce, Gd}–Zr–Sb systems revealed several new ternary compounds and confirmed the known ones. The crystal structure of the new compound Ce0.08(3)Zr1.92(3)Sb was determined from X-ray powder diffraction data. The other new compounds in the Ce–Zr–Sb system were found to have compositions close to ~CeZrSb4and ~Ce2Zr3Sb5. In the Gd–Zr–Sb system the existence of a large homogeneity range was established for the GdZrSb compound along the isoconcentrate 33.3 at.% Sb: Gd1-xZr1+xSb (x= 00.905(18) at 600°C), and a new compound, ~Gd3Zr3Sb14, was discovered. The crystal structures at the boundary compositions of the Gd1-xZr1+xSb phase were refined from X-ray powder diffraction data.

Phase equilibria of the Al-Mn-Sn system were investigated by means of x-ray powder diffraction, scanning electron microscopy and energy dispersive spectroscopy. Two isothermal sections of the Al-Mn-Sn system at 450 and 800 °C were experimentally established. No ternary compound was found at those two temperatures. The low-temperature phase Mn3Sn2 was observed at 450 °C. The solubility of Al in Mn3Sn, Mn3Sn2, MnSn2 and that of Sn in Al8Mn5 at 450 °C is about 3.1, 2.9, 0.6, and 1.7 at.%, respectively. The high-temperature phase Mn2-xSn was observed at 800 °C. The solubility of Al in Mn3Sn, Mn2−xSn and that of Sn in Al8Mn5 at 800 °C was measured to be 2.8, 3.6 and 1.0 at.%, respectively. Al12Mn, also named G phase, was proved to be stable at 450 °C.

In this work, the phase relationship of V-Si-Y ternary system at 1073 K has been experimentally investigated using the combination of x-ray powder diffraction and scanning electron microscopy with energy-dispersive x-ray analyses using equilibrated alloy method. The existence of eight binary compounds, namely, VSi2, V6Si5, V5Si3, V3Si, Y3Si5, YSi, Y5Si4, and Y5Si3 has been confirmed. Y2Si3 and YSi2 were not found at 1073 K. No ternary compound was found at 1073 K in this system. The maximum solid solubility of Si in the (V) phase is about 4.0 at.%. The range of homogeneity of V3Si was from 20.4 to 25.4 at.% Si. No remarkable solid solubility of the elements in any other phase was observed. This isothermal section consists of nine three-phase regions, 19 two-phase regions and 11 single-phase regions.

The crystal structure of the new ternary aluminide Sc1.33Pd3Al8was refined by the Rietveld method from X-ray powder diffraction data. It crystallizes with a Gd1.33Pt3Al8-type structure:hR51-14.00,R-3m,a= 4.29142(4),c= 38.1638(4) Å,RB= 0.0344. The main feature of the structure is the statistical distribution of Sc atoms and Al3triangles within atomic layers of composition Sc2Al3(Sc0.67Al within the translation unit here), which is likely to correspond to stacking disorder of ordered layers. During the final cycles of the refinement, the occupancies of the corresponding sites were fixed at occ. = 2/3 for Sc in Wyckoff position 6cand occ. = 1/3 for Al in 18h. The unit cell of Sc1.33Pd3Al8contains six Sc0.67Al layers, nine Pd and eighteen Al atom layers along the crystallographic direction [001]. Together with the structure types Tb0.67PdAl3, Y2Co3Ga9, Sc0.67Fe2Si5, Er4Pt9Al24, Yb0.67Ni2Al6, and ErNi3Al9, the structure type Gd1.33Pt3Al8forms a family of intergrowth structures built up of three kinds of similar monoatomic layer.

In this paper, we report results on the processing of cadmium zinc sulfide (CdxZn1-xS) ternary compound starting from the deposition of cadmium sulfide (CdS)/zinc sulfide (ZnS) bi-layers buffer configuration and a subsequent thermal annealing for its application to thin film solar cells. The impact of different CdS/ZnS bi-layers buffer configurations as effective alternative to the single CdS buffer layer, as well as the physical and chemical properties of the equivalent CdxZn1-xS ternary compound are presented and discussed. Results on physical properties optimization of CdxZn1-xS ternary compound for future applications to thin film solar cells are presented.

Cesium lead iodide (CsPbI3) has been prepared by a new experimental hazard free precipitation technique. X-ray diffraction spectra have been interpreted with Rietveld refinement which assures the orthorhombic phase of CsPbI3. Energy dispersive X-ray fluorescence spectra confirms the formation of ternary compound. Orthorhombic to cubic phase transition has been studied by observing hysteresis loop in R(T)-T plot for forward-reverse temperature scan. The intra-grain and inter-grain contribution of CsPbI3 to dielectric relaxation has been accounted by fitting the complex impedance plot (Cole-Cole plot). The value of FWHM in Z″(ω)-lnf or M″(ω)-lnf plot is greater than 1.141 decades which reveals the non-Debye type relaxation within material. The broad relaxation peak signifies that there is a distribution of relaxation time over a mean value. Moreover, Z″ & M″ have been plotted in scaled coordinate to check whether the distribution of relaxation time is temperature dependent or not. The frequency dependent relative permittivity represents the decreases of polarizations with frequency which have been successfully analyzed by Koop's theory. Here, activation energies are equal for different formalism, suggests that the same type charge carriers involved in conduction as well as relaxation process. Ac conductivity has been interpreted by using Jonncher's power law and frequency exponent (n) increases with temperature which suggests the presence small polaron hopping mechanism.

The isothermal sections of the phase diagrams of the Lu–V–Ge and Lu-V-Sn ternary systems were constructed at 870 K over the whole concentration range using X-ray diffraction and EPM analyses. In the Lu-V-Ge system a formation of the substitutional solid solution Lu5Ge3-xVx based on the Lu5Ge3 binary compound (Mn5Si3 structure type) was found up to 6 at. % V. Insertion of the V atoms in the structure of the LuGe2 binary germanide (ZrSi2 structure type, up to 5 aт. % V) results in the formation of the LuV0,15Ge2 ternary phase (CeNiSi2 structure type, space group Cmcm, a=0.40210(4), b=1.5661(1), c=0.38876(3) nm), which corresponds to the limit composition of the interstitial solid solution LuVxGe2. The interaction between the elements in the Lu-V-Sn system results in the formation of one ternary compound LuV6Sn6 (SmMn6Sn6-type, space group P6/mmm, a=0.5503(2), c=0.9171(4) nm) at investigated temperature.

The phase equilibria of the Co-Cu-Mo ternary system at 900 and 1100 °C have been studied by using x-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS). Three and five three-phase regions have been confirmed in the system at 900 and 1100 °C, respectively. No ternary compound has been found in these two isothermal sections. At 900 °C, the maximum solubilities of Co and Cu in the μ phase are 56.5 and 4.4 at.%, respectively. As the temperature rises to 1100 °C, their solubilities decrease slightly. Moreover, with the temperature increases from 900 to 1100° C, in the αCo phase, the solubility of Mo increases from 6.5 to 11.9 at.% and the solubility of Cu increases from 8.3 to 12.1 at.%.

Copper indium diselenide (CuInSe2) is a prototype ternary compound and group I–III–VI semiconductor with useful optoelectronic properties. CuInSe2 nanocrystals have been of significant interest because of their size-tunable optical properties and lack of toxic heavy metals. Because of the particular vacancy and antisite substitutional point defects in CuInSe2, large stoichiometric deviations can be tolerated, sometimes leading to the so-called ordered vacancy compounds (OVCs). Here, we use Raman spectroscopy of oleylamine-capped CuInSe2 nanocrystals and ab initio lattice dynamics modeling to study the concentration and arrangements of (2vCu– + InCu2+) defect pairs in the nanocrystals. The nanocrystals have randomly distributed defect pairs that become mobile under light excitation and accumulate, as in OVCs, along the [100] direction. Because the high concentration of vacancies in CuInSe2 nanocrystals is compensated by InCu2+ antisite defects, these nanocrystals do not exhibit an optical plasmon resonance...

Under the first-principles framework, this paper used the CASTEP program to theoretically calculate TiN, TiC, and its intermediate compounds and therefore obtain a theoretical basis for their application. In this paper, the N atoms in the NaCl-type unit cell of TiN were replaced, and the atoms of TiN1-xCx (x = 0.25, 0.5, and 0.75) were constructed by replacing N with C atoms. The unit cell structure of the ternary compound TiN1-xCx (x = 0.25, 0.5, and 0.75) was constructed by replacing N with C atoms. In a subsequent step, these compounds were geometrically optimized and their properties were calculated. These compounds were subsequently subjected to geometric optimization to calculate their properties. By analyzing the electronic structure of the materials, it was found that TiN1-xCx exhibited metallic properties. In addition, this paper focused on the optical properties of TiN1-xCx ternary compounds under different compositions including absorption, reflectivity, refractive index, and photoconductivity. The accuracy and reliability of the theoretical results presented herein were confirmed by comparing current theoretical results with existing experimental or theoretical results.

The liquidus surface projection and isothermal section at 1273 K of the Ni–Ti–V system were established using X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersion spectroscopy (EDS), electron probe micro-analyzer (EPMA) and differential thermal analysis (DTA) techniques. Six primary solidification regions and four invariant reactions were deduced in the liquidus surface projection, and six three-phase regions were derived in the isothermal section at 1273 K. No ternary compound was observed. According to the experimental results in the present work and literatures, the Ni–Ti–V system was modeled by means of the CALPHAD (CALculation of PHAse Diagram) method. Two-sublattice model (Ni,Ti)10(Ni,Ti)20 for binary σ phase was used, and the thermodynamic parameters of the σ and NiV3 phases in the Ni–V system was reassessed. Solution phases (liquid, fcc, bcc and hcp) were modeled with the substitutional solution model in the Ni–Ti–V system. The compounds, Ni3Ti, NiTi2, Ni3V and σ, were treated as (Ni,Ti,V)m(Ni,Ti,V)n, and B2 were treated as (Ni,Ti,V)0.5(Ni,Ti,V) 0.5Va3. A set of self-consistent thermodynamic parameters of individual phases was obtained.

The development of efficient non-noble bifunctional electrocatalysts for the overall water splitting is a pressing and challenging task. In this work, we report a sea urchin-like cobalt phosphosulfide (CoPS) ternary compound for overall water splitting. Because CoPS contains more than one nonmetallic element, ternary compounds possess dianions might lead to modulated electronic structure and thus modified their electrocatalytic properties. Our DFT calculation results reveal that the ternary CoPS exhibits favorable performance for both the oxygen evolution reaction and hydrogen evolution reaction. Experimentally set as cathode and anode in a full cell for overall water splitting, the CoPS cell needs a voltage of only ∼1.59 V to reach a current density of 10 mA cm−2 and has outstanding stability. Our results open up a path to search for alternative bifunctional electrocatalyst materials to substitute for noble metals in overall water splitting.

In this work, we introduce the growth of a new complex oxide lead oxy-chalcogenide (PbOxSe1–x) thin film using an oxygen plasma-assisted molecular beam epitaxy method. Freshly cleaved BaF2(111) wafers were used as the substrates for this growth study. Systematic characterization of X-ray diffraction peaks, Raman shifts, absorption spectra, scanning electron microscopic imaging, and Hall measurements were conducted to elucidate the structural, optical, and electric properties of the as-grown PbOxSe1–x thin films. Specifically, X-ray diffraction measurements revealed that PbOxSe1–x films maintained the same rock-salt crystal structure as the PbSe semiconductor, but a slight shift in the lattice parameter was observed. A blue shift in the optical absorption edge also suggests that the inclusion of oxygen atoms led to the formation of a ternary compound crystal structure. Furthermore, all PbOxSe1–x thin films were observed to be polycrystalline in nature and displayed preferred [100] orientated grains. Slight...

To reduce the viscosity of viscous crude oil and flow resistance, the effect of a ternary compound system including organic alkali, n-alkanol, and nonionic surfactants on viscous crude oil viscosit...

Ternary compound Cu2SnS3 (CTS) was fabricated by simple, low cost and high efficient spray pyrolysis and rapid thermal annealing route. The influences of annealing temperature and annealing duration on the properties of the prepared CTS thin film were investigated in detail. X-ray diffraction spectrometer, Scanning Electron Microscope, UV–Vis–IR spectrophotometer and I–V test system were employed for the analysis of the structural, morphological, optical and photoelectric properties of the prepared CTS thin film, respectively. The characterization results show that the CTS thin film prepared under the optimal annealing condition of 500 °C and 15 min presents as tetragonal structure with preferential (1,1,2), bandgap value of 1.44 eV, crystal grain size of around 80 nm and photoelectric conversion efficiency as high as 1.24%.

Considerable efforts have been made to develop hematite as a promising material for photoelectrochemical (PEC) water splitting. However, the fast recombination of carriers in the bulk and on the surface greatly constrains the solar-to-chemical fuel conversion efficiency. Herein, a precise method was utilized to alleviate the recombination by constructing p-n junction of CaFe2O4/α-Fe2O3 and further modifying with Co3O4. The structural information and chemical composition of the ternary compound were systematically characterized. The photocurrent density at 1.23 V vs RHE (reversible hydrogen electrode) of the photoanode increased by five times compared to the bare α-Fe2O3, and the onset potential also shifted negatively to 0.6 V vs RHE. The formation of p-n junction and surface Co3O4 modification were proven to enhance the charge separation in the bulk and on the surface, respectively. Also the Co3O4 played a bifunctional role of passivating the surface states and accelerating the water oxidation kinetics.

The toxicity of the organic dyes presents in the environment due to polluted discharge from industries is a real dilemma in the world. Here, the problem was addressed with the synthesis of new quaternary mineral cupric antimony oxychloride (CAO) during the study of Cu–Sb–O–Cl system in absence of solvents. The morphological analysis showed that synthesized matrix is rough and uneven with round and cylindrical shapes. The composition of nanomaterial verified the elemental composition as Cu, Sb and Cl. The XRD analysis revealed that synthesized product CAO is crystalline in nature where crystallite size was estimated in the range of 2–8 nm. The bond vibrations were studied through Fourier transforms infrared spectroscopy to confirm the symmetric and asymmetric vibrations in the matrix. The material parameters (grain size, dislocation line density, stresses and miller indices) of the synthesized material CAO were calculated using powder X-ray diffraction analysis. Thermogravimetric analysis was performed to study the decomposition behaviour and stability of the CAO. The copper ternary compound was used to mitigate the effect of organic dyes like Sunset yellow (26%), Methylene blue (23%), Brilliant green (20%), Methyl orange (14%) in the dyes polluted wastewater.

Following the recent determination of the Al3AuIr structure, a new ternary phase has been identified in the Al–Au–Ir phase diagram. It has a chemical composition Al9(Au;Ir)4 with an apparently low gold content. Its crystal structure has been determined with single-crystal X-ray diffraction. The new compound crystallizes in the tetragonal crystal system and has been successfully solved in space group I41/acd (Pearson symbol tI104) with lattice parameters a = 8.6339 (2) and c = 21.8874 (7) Å. Atomic environments are described as well as similarities with the BGa8Ir4 compound.

Research shows that the viscosity greatly reduction of viscous crude oil can improve the exploitation and promote the fluidity. We studied the effects and the mechanism of viscosity reduction of vi...

Investigation of the electronic structure of ZnSnAs2, a semiconducting ternary compound and its optical properties has been made to showcase its usefulness in the field of photonic devices. The computational electronic property calculations like density of states, energy bands, dielectric tensor’s real and imaginary component and optical properties like absorption coefficient, reflectivity and refraction have been performed using generalized gradient approximation within the full potential linearized augmented plane wave method. Our computations reveal that ZnSnAs2 has a direct band gap of 0.42 eV. Inter-band transitions are the elaboration of the peaks arising from the origin in a dielectric tensor’s imaginary component. The notable intensity lying between energy ranges 3–5 eV in spectra of absorption presents use of such compounds in various optoelectronic devices.

The 800 °C isothermal section in the Al-Zn-Zr system was investigated using the equilibrated alloy method and the solid/liquid diffusion couple approach by means of scanning electron microscopy equipped with energy dispersive spectroscopy, X-ray powder diffraction and electron probe microanalysis. Thirteen three-phase regions are experimentally confirmed in the ternary system. A ternary compound Zn50Al25Zr25 named as T phase exists stably in the 800 °C isothermal section. Its composition range varies widely (16.84-55.1 at.% Zn, 18.02-56.3 at.% Al and 26.0-28.53 at.% Zr), and it can be in equilibrium with all the binary compounds. The maximum solubilities of Zn in Zr3Al, Zr2Al, Zr3Al2, Zr4Al3, ZrAl, Zr2Al3, ZrAl2 and ZrAl3 are 7.5, 0.84, 0.33, 0.89, 0.91, 1.12, 0.64 and 3.8 at.%, respectively. The maximum solubilities of Al in Zn3Zr, Zn2Zr and ZnZr are 1.6, 1.3 and 13.6 at.%, respectively.

Ternary compound semiconductor CdSexS1-x (x = 1, 0.8, 0.6, 0.4, 0.2 and 0) thin films were prepared on glass substrates by using simple solution processed spin coating technique. Cadmium acetate, sodium selenosulfate and thiourea were used as source materials for Cd2+, Se2− and S2− ions, while triethanolamine was used as a capping agent. The 25% concentred NH4OH solution was used as a complex reagent and also used to adjust the pH of the final solution ~ 11. The deposition conditions (rotation speed 2000 rpm for 30 s and substrate dried in the air at 120 °C for 2 min) were remain same for all the samples. The as-deposited thin films on glass substrate were annealed at 350 °C for 30 min. The X-ray diffraction pattern shows that all the samples were polycrystalline in the nature with hexagonal structure. The most of prepared thin films were highly textured along (002) plane and peak position for plane (002) is shifted with change in composition ‘x’. The average crystallite size in CdSexS1-x thin films were found between 62.6 nm to 93.4 nm. Scanning electron microscopy images showed uniform deposition morphology with spherical shaped grains distributed over entire glass substrate. Samples CdSe0.8S0.2 and CdSe0.6S0.4 thin films indicated interesting morphological features with the combination of spherical shaped nanoparticles and interconnected nanofibers which form hierarchical flowerlike microstructure. Energy dispersive X-Ray studies confirmed that thin films were having approximately same stoichiometry of atomic ratio of elements Cd, Se and S as present in volumetric ratio of the reactants in chemical solution. Fourier transform infrared studies confirmed the formation of the Cd(Se,S) bonding in materials. The optical band gap of CdSexS1-x thin films were found as direct band gap in the range of 1.82 eV to 2.32 eV. As the incorporation of sulphur element increases, the band gap of CdSexS1-x thin film also increases. The CdSexS1-x thin films can be used as absorption layer in solar photovoltaic cell which is due to wide and fine tenability of the energy band gap.

The phase formation of Ti–Al–C powder mixtures with compositions close to MAX phases during self-propagating high-temperature synthesis (SHS) is investigated using time-resolved X-ray diffraction. It is found that the formation of the material during combustion in air under low heat-removal rates is a staged process. At the first stage, the dominant reaction is titanium carbide formation, providing major heat release and combustion front propagation. This reaction leads to the formation of TiC crystals surrounded by the Ti–Al melt. Titanium carbide is dissolved in the surrounding melt behind the combustion front with the subsequent crystallization of the Ti2AlC ternary compound. No TiC formation is observed during synthesis in helium, which provides rapid heat removal. The first phase appearing in the diffraction field is Ti2AlC. The TiC life cycle of 5–10 s for the mixtures synthesized in air substantially decreases when performing the process in helium and does not exceed 1 s. SHS leads to the formation of the composite material based on Ti2AlC phase containing less than 20 wt % TiAl and 2 wt % TiC. The material structure is characterized by lamellar Ti2AlC grains surrounded by the TiAl matrix. The microhardness of synthesized materials is 4.0–4.5 GPa and corresponds to the microhardness of the Ti2AlC phase. The dispersity of Ti2AlC grains during the synthesis in helium is lower than during the synthesis in air. Lamellar MAX-phase grains grow to 8–15 μm in length and 2–5 μm in width during slow cooling in air. The dispersity of Ti2AlC grains grown in helium is lower, being no larger than 8 and 1 μm, respectively.

Phase diagram of the Bi-Ce-Ge ternary system has been investigated experimentally and thermodynamically extrapolated by using Pandat software. Experimental results were obtained using differential thermal analysis (DTA), scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS), and X-ray powder diffraction (XRD) methods. Examined ternary samples belong to two isothermal sections at 400 and 600 °C as well as three vertical sections Bi-CuGe, Cu-BiGe, and Ge-BiCu. No ternary compound has been detected in the equilibrated samples from the selected isothermal sections. Based on the presented experimental data and available literature data, description of the ternary system has been developed. A reasonable agreement between the experimental data and the calculated phase equilibria was obtained. As an example, ternary Cu80Bi10Ge10 alloy was selected for solidification simulations according to Scheil and Lever Rule assumptions as well as for simulation of the total fraction of each solid at different temperatures, latent heat, and total heat.

Heterovalent ternary nitrides are considered one of the promising classes of materials for photovoltaics, combining attractive physical properties with low toxicity and element abundance. One of the front‐runner systems under consideration is ZnSnN2. Although it is nominally a ternary compound, no clear crystallographic evidence for cation ordering has been observed so far. An attempt to elucidate this discrepancy [Quayle (2020). Acta Cryst. A76, 410–420] was the trigger for an intensive discussion between the authors, and an agreement was reached to elaborate on some points in order to set things in perspective. Rather than using a conventional comment–answer scheme, this is published in the form of a joint discussion to celebrate constructive criticism and collegiality., A scientific exchange on an earlier paper [Quayle (2020). Acta Cryst. A76, 410–420] has led to the clarification of some of the points. image

The earth abundant ternary compound BaZrS3, which crystallizes in theperovskite type structure, has come into view as a promising candidate for photovoltaicapplications. We present the synthesis and characterization of polycrystalline perovskite typeBaZrS3thinfilms. BaZrO3precursor layers were deposited by pulsed laser deposition andsulfurized at various temperatures in an argon diluted H2S atmosphere. We observe increasingincorporation of sulfur for higher annealing temperatures, accompanied by a red shift of theabsorption edge, with a bandgap ofEg 1.99 eV and a large absorption strength gt;105cm amp; 8722;1obtained for sulfurization temperatures of 1000 C. X ray diffraction analysis and SEM indicateenhanced crystallization at the higher annealing temperatures, but no evidence for a crystallinesolid solution between the BaZrO3and BaZrS3phases is found. The charge carrier summobility estimated from optical pump amp; 8722;terahertz probe spectroscopy indicates increasingmobilities with increasing sulfurization temperature, reaching maximum values of up to amp; 8764;2cm2V amp; 8722;1s amp; 8722;1

The ternary intermetallic compound SbSnTi is known for a reversible uptake of Li at low potentials versus pure Li and is therefore a candidate as anode material for use in Li-ion batteries (LiBs). Up to now, no phase diagram data for the ternary Sb-Sn-Ti system have been reported in literature, which is, however, crucial for the understanding of the lithiation process. In this work isothermal sections of this system at 600 °C, 800 °C and 1000 °C were acquired for the first time. They are based on powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM/EDX) investigations of alloy samples. During our investigations two new ternary phases, SbxSn19-xTi15 and (SbxSn1-x)3-yTi5+y, were recognized from PXRD patterns; the crystal structures were subsequently determined by single-crystal X-ray diffraction. SbxSn19-xTi15 crystallizes with the cubic space group Pm-3 (No. 200), the lattice parameter is a = 8.8502 A. (SbxSn1-x)3-yTi5+y shows tetragonal symmetry with the lattice parameters a = 10.553 A and c = 5.3982 A and the space group I4/mcm (No. 140). A further ternary compound, Sb4SnTi5, could be identified; its incommensurate crystal structure could not yet be fully described.

En esta tesis se presenta un estudio en profundidad del crecimiento cristalino y la caracterización de algunos materiales funcionales de la familia II-VI. Las propiedades estructurales, morfológicas, ópticas y eléctricas estudiadas se han correlacionado con la metodología y condiciones de crecimiento cristalino utilizadas. Entre la variedad de materiales II-VI, se han elegido 2 familias de semiconductores debido a sus propiedades singulares. El primero incluye los óxidos del grupo II, con elementos como el Zinc y el Cadmio, con una alta transparencia en el rango óptico visible. Estos compuestos se pueden usar en diversas aplicaciones en optoelectrónica, incluyendo su uso como óxidos conductores transparentes (TCO). El otro conjunto de materiales estudiados son algunos semiconductores magnéticos diluidos (DMS) basados en los compuestos ZnS y ZnTe con Manganeso que además de las propiedades semiconductoras habituales, tienen propiedades magnéticas interesantes. Con el fin de crecer los compuestos binarios y ternarios estudiados en esta tesis, se han utilizado dos métodos de crecimiento: un sistema de deposición CVD basado en la descomposición de compuestos metal-orgánicos (MOCVD), técnica con control multiparamétrico y un método más simple como es la sublimación en vacío a corta distancia (CSVS). De acuerdo con los objetivos de la tesis, la caracterización de las muestras se ha realizado utilizando las siguientes técnicas: microscopía de fuerza atómica (AFM), microscopía electrónica de barrido (SEM) y microscopía electrónica de transmisión (TEM), análisis de difracción de rayos-X (XRD), espectroscopía dispersiva de rayos-X (EDX), mediciones de emisión de rayos-X inducida por partículas (PIXE) y medidas de reflectividad y transmision óptica. Así pues, se crecieron capas delgadas de ZnO mediante el método MOCVD sobre diferentes planos de corte del zafiro. La banda prohibida directa del ZnO (~ 3.4 eV) proporciona un buen grado de transparencia óptica en la region visible del espectro electromagnético, y sus propiedades piezoeléctricas son ideales para la aplicación en filtros de ondas acústicas de superficie (SAW). El uso de este material en campos como la fotónica y la microelectrónica hace que la obtención de capas de espesor nanométrico, manteniendo una buena calidad morfológica y estructural, sea un desafío fundamental. En esta tesis se ha realizado un estudio sistemático de la disminución del espesor y rugosidad de las capas de ZnO en función de las condiciones de crecimiento (flujo del precursor, temperatura de crecimiento y tiempo de crecimiento). De manera complementaria se ha realizado un tratamiento químico del sustrato con el objetivo de aumentar los puntos de nucleación. Este estudio sistemático ha resultado en el logro y caracterización de capas de alta calidad con espesores de aproximadamente 34 nm y una rugosidad del orden de 2 nm. Teniendo en cuenta la posibilidad de cambiar las propiedades de los compuestos binarios (como la densidad de portadores o la energía del bandgap) mediante la aleación del material con otro elemento, se llevó a cabo el crecimiento de la aleación CdZnO. Una de las principales dificultades para obtener este compuesto ternario con propiedades deseables y buena calidad cristalina es la debida a la diferencia entre las estructuras cristalinas del ZnO (wurtzita) y el CdO (cúbico). La mayor parte del trabajo que se puede encontrar en la literatura está dedicado a compuestos ternarios con un alto contenido de zinc o cadmio, mientras que el estudio de la transición entre las fases cúbica y wurtzita ha recibido menos atención. En esta tesis hemos profundizado en el crecimiento de la región rica en cadmio de la aleación sobre R-zafiro, mostrando el límite de solubilidad del Zn, en las condiciones experimentales analizadas, y cómo la transición de la fase cúbica a una en la que coexisten ambas fases afecta a las propiedades estructurales de este compuesto ternario. Además, se ha analizado la influencia del gas portador sobre las características estructurales y ópticas de las capas delgadas obtenidas. En el mismo marco de estudio de la familia II-VI, el CdTe ocupa un lugar de privilegio. Este material se utiliza a menudo como capa absorbente en heteroestructuras de CdTe/CdS. Por otro lado, las heteroestructuras con TCO, en particular la heterounión p-n CdTe/CdO, han sido menos estudiadas. La complejidad en la obtención de esta heteroestructura se debe, entre otros factores, al desajuste de red entre el CdO y el CdTe. Los parámetros de crecimiento se eligieron de tal manera que las tensiones entre las capas de la heteroestructura de CdTe/CdO/R-zafiro crecida por el método MOCVD se minimizaran. El estudio de la diferencia de potencial de contacto (CPD) y el cambio en el fotovoltaje superficial (SPV) en función de la potencia aplicada del láser incidente, se han analizado en correlación a la temperatura de crecimiento. Por otro lado, los DMS combinan elementos de la física de los semiconductores y el magnetismo, lo que constituye una oportunidad única para la investigación y la tecnología. A diferencia de las aleaciones de semiconductores clásicas, la distribución aleatoria de iones magnéticos conduce a la aparición y desarrollo de fases magnéticas individuales. La inclusión de átomos de Mn en la red II-VI es particularmente interesante ya que conduce a fenómenos como la magnetorresistencia negativa, la rotación de Faraday gigante y el comportamiento del vidrio de spin. Así, hemos estudiado el crecimiento y caracterización de la aleación de ZnS y ZnTe con Mn, debido a la banda prohibida ancha que presentan y a las características ópticas derivadas que pueden presentar estas aleaciones, que las hace atractivas para aplicaciones fotovoltaicas. Así, hemos obtenido capas delgadas de ZnMnTe y ZnMnS sobre vidrio mediante la técnica CSVS. Nuestro estudio mostró el límite de solubilidad del Mn en nuestras condiciones experimentales, y cómo la incorporación de manganeso afecta las características estructurales, subestructurales y ópticas de los correspondientes compuestos ternarios. This thesis presents an in-depth study of the crystal growth and characterization of some functional materials of the II-VI family. The studied structural, morphological, optical and electrical properties have been correlated with the crystal growth methodology and growth conditions used. Among the variety of II-VI materials, 2 groups of semiconductors have been chosen due to their unique properties. The first includes oxides of II-group, with elements such as Zinc and Cadmium, with high transparency in the visible optical range. These compounds can have applications in optoelectronics and can be used as transparent conductive oxides (TCOs). The other group of studied materials is some diluted magnetic semiconductors (DMS) based on Manganese and the II-VI semiconductors ZnS and ZnTe. In addition to the usual semiconductor properties, the Mn alloyed materials can have interesting magnetic properties. In order to grow the binary and ternary compounds studied in this thesis, two growth methods have been used, the more accurate, multiparameter-controlled Metal-Organic Chemical Vapor Deposition (MOCVD) method and the simpler Close Space Vacuum Sublimation (CSVS). The characterization of the samples has been done using the following techniques: atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy (EDX), particle-induced X-ray emission (PIXE) and optical reflectance and transmission measurements. Thus, ZnO thin films were grown using the MOCVD method on the crystal planes C-, A-, M- and R- of sapphire substrates. The ZnO direct bandgap of ~ 3.4 eV provides a good degree of optical transparency in the visible region of the electromagnetic spectrum, and its piezoelectric properties are ideal for application on surface acoustic waves (SAWs) filters. Moreover, ZnO has shown its potentiality in fields such as photonics and microelectronics. In this regard, obtaining layers of nanometric thickness, while maintaining a good morphological and structural quality, is both a requirement and a challenge. In this thesis, a systematic study of the thickness and roughness decrease of the ZnO layers has been undertaken as a function of the growth conditions (precursor flux, growth temperature and time). In a complementary manner, a chemical treatment of the substrate has been carried out, in order to increase the nucleation points. This systematical study has resulted in the attainment and characterization of high-quality layers with thicknesses of about 34 nm and roughness of about 2 nm. Taking into account the possibility of changing the properties of binary compounds (such as the carrier density or bandgap energy) by alloying the material with another element, the growth of the CdZnO alloy was carried out. One of the main difficulties in obtaining this ternary compound with desirable properties and good crystal quality is due to the difference in crystal structures between ZnO (wurtzite) and CdO (cubic). Most of the works that can be found in the literature are devoted to the ternary with high content of zinc or cadmium, while the study of the transition between the cubic and wurtzite phases has received less attention. In this thesis, we have delved into the growth of the cadmium rich region of the alloy on R-sapphire, and we have found the solubility limit of Zn under our experimental conditions, and how the transition from the cubic phase to a mixed one affects the structural properties of this ternary compound. Additionally, the influence of the carrier gas on some structural and optical features of the CdZnO thin layers has been analyzed. In the same frame of studying the II-VI family, CdTe stands out as one of the most significant of this family. CdTe is often used as an absorber layer in CdTe/CdS heterostructures. Nevertheless, heterostructures with TCO, in particular the p-n-heterojunction CdTe/CdO, have been less studied. The complexity in obtaining this structure is due to, among other factors, the lattice mismatch between CdO and CdTe. In this thesis, the growth parameters were chosen in such a way that the stresses between the layers of the CdTe/CdO/R-sapphire heterostructure grown by the MOCVD method are minimized. The study of the Contact potential difference (CPD) and the change in the Surface photo voltage (SPV) as a function of the applied power of the incident laser have been analyzed in correlation with the growth temperature. On the other hand, DMS, as said before, combine elements of the physics of semiconductors and magnetism, which is a unique opportunity for research and technology. Unlike in classical semiconductor alloys, the random distribution of magnetic ions leads to the appearance and development of individual magnetic phases. Among alloying elements, the inclusion of Mn atoms in the II–VI lattice is particularly interesting since it leads to phenomena such as negative magnetoresistance, giant Faraday rotation and spin glass behavior. We have studied the growth and characterization of the ZnS and ZnTe alloying with Mn, due to the wide bandgap and optical features that these alloys can present, which make them attractive for photovoltaic applications. Thus, ZnMnTe and ZnMnS thin films were obtained on glass substrates by the CSVS technique. The study has shown the Mn solubility limit under our experimental conditions, and how the incorporation of manganese affects the structural, substructural, and optical characteristics of the ternary compounds.

Growth of polycrystalline CdMnTe ternary compound thin films has been carried out using cathodic electrodeposition technique at different cathodic potentials. The range of the cathodic potentials used in this work has been chosen according to the cyclic voltammogram results. The CdMnTe thin films were electroplated from electrolyte containing CdSO4, TeO2 and MnSO4 in an acidic aqueous medium. Glass/fluorine-doped tin oxide (FTO) substrates have been used to electrodeposit the semiconductor layers. The structural, compositional, morphological, optical and electrical properties of the CdMnTe thin films were studied using X-ray diffraction (XRD), Sputtered neutral-mass spectroscopy (SNMS), Scanning electron microscopy (SEM), UV–Vis spectroscopy and Photo-electro-chemical (PEC) cell measurements respectively. The primarily grown as-deposited (AD) layers went through two different post-growth surface treatment conditions- heat-treated in air in the presence of CdCl2 (CCT) and heat-treated in air in the presence of GaCl3 (GCT). Results from the XRD indicated the polycrystalline nature of the electrodeposited films. The electroplated films have cubic crystal structures and the preferred orientation was found to be along the (111) plane of CdMnTe. Inclusion of Mn has been qualitatively observed using SNMS measurement. The optical energy bandgaps of the thin films were found to be varying between ~ 1.90 and ~ 2.20 eV. Though all the layers after post-treatment showed p-type electrical conduction, both p and n-type conductivity were obtained at different cathodic potentials for as-deposited materials. Comparison of the deposited layers to other electrodeposited ternary compounds has also been discussed.

A new ternary compound Cu2SnTi3 has been synthesized by vacuum sintering at 900 &deg, C. The atomic structures of CaCu5- and InNi2-like Cu2SnTi3 are calculated using density functional theory methods. The X-ray diffraction (XRD) analysis and selected area diffraction (SAD) patterns of the new ternary compound Cu2SnTi3 are considered to verify the atomic structures of CaCu5- and InNi2-like Cu2SnTi3. The results reveal that the InNi2-like Cu2SnTi3 model has the lowest total energy of &minus, 35.239 eV, representing the trigonal crystal structure. The orthorhombic crystal structure of the CaCu5-like Cu2SnTi3 model has the second lowest total energy of &minus, 33.926 eV. Our theoretical X-ray diffraction peak profiles of InNi2-like (CaCu5-like) Cu2SnTi3 are nearly identical to experimental one, leading to an error below 2.0% (3.0%). In addition, the hexagonal crystal structure of the CaCu5-like Cu2SnTi3 model has the highest total energy of &minus, 33.094 eV. The stability of the Cu2SnTi3 in terms of energy follows the order: the trigonal, orthorhombic, and hexagonal crystal structure.