Sb System Research Articles

A thermodynamic assessment of the Mg–Sn–Sb ternary system

Magnesium-tin-antimony (Mg–Sn–Sb) system is a promising system for developing high-creep resistance magnesium alloy and the alloy-type anode of magnesium recharge battery. Herein, the thermodynamic assessment of Mg–Sn–Sb ternary system was carried out using the CALculaiton of PHAse Diagram (CALPHAD) approach based on available literature data. The liquid phase was described via the associated model with associates Mg3Sb2 and Mg2Sn, and the compounds were described using the sublattice model. The consistency of the calculated phase equilibria relations and thermochemical properties with the available experimental data of Mg–Sn–Sb ternary system is presented. The thermodynamic descriptions of Mg–Sb, Sn–Sb binary systems and Mg–Sn–Sb ternary system assessed in this work provide a thermodynamic basis for the alloy design of magnesium alloy.

Self-Assembly of Complementary Components Using a Tripodal Bismuth Compound: Pnictogen Bonding or Coordination Chemistry?

Triple pnictogen bonding refers to the ability of a pnictogen atom to engage in three simultaneous pnictogen bonds (PnBs) to a complementary partner through a single pnictogen atom. This supramolecular strategy was recently introduced as a unique facet of pnictogen bonding as compared to other named supramolecular interactions. Here, the ability of bismuth to participate in this phenomenon is demonstrated using Bi((NC9H7)3CH3). The study reveals that Bi engages in stronger PnBs than the analogous Sb system. The results have been contrasted with Bi systems that form strong coordination bonds, and analysis of the electron density along the bond path reveals key differences. The solution behavior of these newly synthesized supramolecules were studied by PFGSE NMR spectroscopy and they are found to remain intact in solution. Molecular design strategies that allow for triple pnictogen bonding should find use in the fields of molecular recognition and crystal engineering.

Thermoelectric Characteristics of Two-Dimensional Structures for Three Different Lattice Compounds of B–C–N and Graphene Counterpart BX (X = P, As, and Sb) Systems

Thermoelectric Characteristics of Two-Dimensional Structures for Three Different Lattice Compounds of B–C–N and Graphene Counterpart BX (X = P, As, and Sb) Systems

Crystal structure characterization and electronic structure of a rare-earth-containing Zintl phase in the Yb-Al-Sb family: Yb3AlSb3.

A rare-earth-containing compound, ytterbium aluminium antimonide, Yb3AlSb3 (Ca3AlAs3-type structure), has been successfully synthesized within the Yb-Al-Sb system through flux methods. According to the Zintl formalism, this structure is nominally made up of (Yb2+)3[(Al1-)(1b - Sb2-)2(2b - Sb1-)], where 1b and 2b indicate 1-bonded and 2-bonded, respectively, and Al is treated as part of the covalent anionic network. The crystal structure features infinite corner-sharing AlSb4 tetrahedra, [AlSb2Sb2/2]6-, with Yb2+ cations residing between the tetrahedra to provide charge balance. Herein, the synthetic conditions, the crystal structure determined from single-crystal X-ray diffraction data, and electronic structure calculations are reported.

Strain-tuned magnetic properties in (Ga,Fe)Sb: First-principles study* *Project supported by the National Natural Science Foundation of China (Grant Nos. 11764032 and 11665018).

In view of the importance of enhancing ferromagnetic (FM) coupling in dilute magnetic semiconductors (DMSs), the effects of strain on the electronic structures and magnetic properties of (Ga,Fe)Sb were examined by a first-principles study. The results of the investigation indicate that FeGa substitution takes place in the low-spin state (LSS) with a total magnetic moment of 1μ B in the strain range of –3% to 0.5%, which transitions to the high-spin state (HSS) with a total magnetic moment of 5μ B as the strain changes from 0.6% to 3%. We attribute the changes in the amount and distribution of the total moment to the influence of the crystal field under different strains. The FM coupling is strongest under a strain of about 0.5%, but gradually becomes weaker with increasing compressive and tensile strains. The magnetic coupling mechanism is discussed in detail. Our results highlight the important contribution of strain to magnetic moment and FM interaction intensity, and present an interesting avenue for the future design of high Curie temperature (T C) materials in the (Ga,Fe)Sb system.

Resistivity superconducting transition in single-crystalline Cd0.95Ni0.05Sb system consisting of non-superconducting CdSb and NiSb phases

Resistivity superconducting transition has been for the first time found in single crystal of two-component 0.95(CdSb)–0.05(NiSb) system. End members of the system are not superconductors under normal conditions. Insulating behavior in temperature dependence of the electrical resistivity, which is due to hopping conductivity, precedes the transition. The resistivity superconducting transition is rather broad, since at cooling down the electrical resistivity starts to fall at 10.5 K, whereas zero resistivity is reached only at ~2.3 K. Longitudinal magnetic field gradually depresses superconductivity and shifts the superconducting transition to lower temperatures. Under magnetic field above 0.5 T, superconductivity is totally destroyed. Main features observed in the resistivity superconducting transition, including its unusually big width and insulating electrical behavior above the transition, can be related to inhomogeneity of the single crystal studied. According to XRD and SEM examinations, the single crystal consists of major CdSb phase and minor NiSb phase. The NiSb phase forms inhomogeneities in the CdSb matrix. Micro-sized needle-like NiSb crystals and nano-sized Ni1-xSbx clusters can be considered as typical inhomogeneities.

Alloy decomposition under pressure: Bi–Sb incommensurate phase as a case study

The high-pressure phase behavior of the Bi–Sb system was investigated experimentally and modeled thermodynamically to study the effect of the transition to the incommensurate Bi-III type structure, which is adopted by the high-pressure phases Bi-III and Sb-II of the pure elements. The thermodynamic model of the Bi–Sb phase diagram including the effect of pressure in the isomorphous regime was extended to include solid–solid phase transitions of the pure elements. Consequently, the alloy phase diagram was found to transform to the eutectic form with pressure and is predicted here in the pressure range of 3–6 GPa. The alloy was found to transform from the ambient, rhombohedral A7 structure to the incommensurate phase. The transformation occurred at intermediate pressures between those observed in elemental Bi and Sb. The region of thermodynamic stability was determined by calculating the spinodal curves. To verify these predictions, the structure of a Sb-rich alloy was determined as a function of pressure by X-ray diffraction measurements in a diamond anvil cell, demonstrating the transition from A7 to the incommensurate Sb-II-like structure. It was found that the decomposition of the alloy under pressure is determined by the thermodynamic instability located at the spinodal curve. In contrast, alloy compositions located in the metastable region between the binodal phase line and the spinodal curve did not decompose under pressure, thus indicating a new region of phase space to be explored in high-pressure studies of alloys.

Experimental and theoretical investigation of the Y–Ni–Sb and Tm–Ni–Sb systems

Interaction of Yttrium and Thulium with Nickel and Antimony was studied at 870 K in the whole concentration range based on XRD and EPM analyses. Four ternary compounds are realized in the Y–Ni–Sb system: Y5Ni2Sb (Mo5SiB2-type), Y5NixSb3-x (Yb5Sb3-type), YNiSb (MgAgAs-type), and Y3Ni6Sb5 (Y3Ni6Sb5-type). At 870 K the Tm–Ni–Sb system is characterized by the formation of two ternary antimonides: Tm5Ni2Sb (Mo5SiB2-type) and TmNiSb (MgAgAs-type). Temperature dependencies of the electrical resistivity and Seebeck coefficient of the YNiSb and TmNiSb half-Heusler compounds were measured in the temperature range 80–380 K. Both compounds behave as doped and compensated semiconductors. The DFT calculations were performed for the ordered and disordered models of YNiSb to explain the homogeneity region and transport properties.

Ag–Sb/Cu interfacial reactions and Ag–Cu–Sb phase equilibria

Ag–Sb alloys are promising materials in joining applications and Cu is frequently encountered in electronic and thermoelectric devices. This study examines the Ag-41.0 at%Sb/Cu interfacial reactions and the phase equilibria isothermal sections of Ag–Cu–Sb at 300 °C and 500 °C. The Ag–Sb eutectic is reexamined and is at Ag-42.0 at%Sb and at 484.5 °C. No ternary compound is observed in the Ag–Cu–Sb system. It is found the ternary solubilities in the binary compounds in the Ag–Cu–Sb system are not significant. The highest is 4.7 at.% Cu in the Ag7Sb compound. Two reaction phases, Cu2Sb and Ag3Sb, are formed in the Ag–Sb/Cu couples reacted at 300 °C. Three reaction phases, Cu2Sb, Cu3Sb and Ag3Sb, are formed in the Ag–Sb/Cu couples reacted at 500 °C. The reaction rate in the couples reacted at 500 °C is very fast, and the reaction layer is 89 μm thick in the couple reacted for 4 min.

Intermetallic Compounds NakMn (М = K, Cs, Ba, Ag, Pt, Au, Zn, Bi, Sb): Geometrical and Topological Analysis, Cluster Precursors, and Self-Assembly of Crystal Structures

A geometrical and topological analysis has been performed, and self-assembly of the crystal structures of intermetallic compounds formed in the Na–M (M = K, Cs, Ba, Ag, Pt, Au, Zn, Bi, Sb) systems has been simulated using computer methods (the ToposPro software). The NakMn precursor metal clusters of the crystal structures are determined based on the algorithms of structural-graph decomposition in cluster structures and construction of the basic net of the structure in the form of a graph whose nodes correspond to the cluster centers. The tetrahedral metal clusters M4, forming packets in the Na3Bi-hP8, Na2Bi2-tP4, and Na2Sb2-mP16 crystal structures; tetrahedral metal clusters M4 and spacers for the Na2(Au4)-cF24 and Ba2(Na4)-hP12 framework structures; octahedral clusters M6 for the Na4Au2-tI12 structure; octahedral M6 and tetrahedral M4 metal clusters for the Na2(Na4)(Ba6)-cF96 and Au2(In4)(Na6)-cF96 structures; and icosahedral metal clusters M13 for the Na(Zn13)-cF116 structure are found. The symmetry and topology code of the self-assembly of crystal structures of NakMn intermetallic compounds has been reconstructed from precursor metal clusters $$S_{3}^{0}$$ in the following form: primary chain $$S_{3}^{1}$$ → microlayer $$S_{3}^{2}$$ → microframework $$S_{3}^{3}$$ .

Interdiffusion Studies in the Co-Sb System

CoSb based compounds have gained much importance in the fields of thermoelectric devices. In this work, we have conducted the solid–state conventional bulk diffusion couple experiments. To study the phase evolutions, Co/Sb diffusion couples are annealed at 450–550 °C. The interdiffusion zone is analysed using field emission gun equipped scanning electron microscope and the composition measurements are done in electron probe micro−analyser to confirm the growth of various product phases. The marker experiment indicates that the CoSb3 phase grows mainly by diffusion of Sb in the binary Co–Sb system. Growth of the CoSb3 phase is discussed based on assessment correlating the difference in mobilities of species with the high homologous temperature, crystal structure of the phase, and the concept of sublattice diffusion mechanism in line compounds.

Multi-element receiver with semimetal film sensing element for the submillimeter thermal imagers of viewing type

Prospects of developing multi-element receivers for the submillimeter range (SMM) on the basis of thin-film semimetallic sensitive bolometers are considered. Electromagnetic waves of the SMM band have a high penetrating power and allow developing a thermal imager for the detection and observation of objects through various materials: fabrics, cardboard, wood, etc. The previously obtained research results are summarized. On the basis of the theoretical and experimental studies and of a review of scientific, technical and patent literature, in this work, a thermoresistive converter based on single-crystal films of materials in the metal – narrow-bandgap semiconductor – dielectric transition state is selected as a sensitive element. To determine the possibilities of using thinfilm Bi and Bi–Sb system as an absorber of terahertz radiation, as well as a polyimide film as an absorption-enhancing antireflection coating, the transmission spectra and reflection spectra of single-crystal Bi films grown on a 12 μm thick polyimide substrate were measured. The measurements were performed on a setup using selective radiation reception at cyclotron resonance absorption in InSb, which records the thermal radiation of material samples in the range from 1 to 5 THz with a spectral resolution of 0.6 THz. The design and characteristics of the model receiver are presented. The experimental setup was performed using a terahertz gas-discharge laser. The NEP of the proposed receiver is ~(4 ÷ 6)∙10 –11 W/Hz 1/2 .

The TbNiIn1-xMx (M = Al, Ge, Sb) systems

Interaction of the components in TbNiIn 1- x Al x , TbNiIn 1- x Ge x and TbNiIn 1- x Sb x systems at 873 K was investigated by means of X-ray phase and partially local analysis in full concentration range. The samples for the investigation were synthesized by arc-melting purity metals with subsequent annealing at 873 K for a month. Phase analysis was carried out by X-ray powder diffraction (DRON-2.0M, Fe K α-radiation, PANalytical X’Pert Pro, Cu K a- radiation, Guinier FR552, Cu K a-radiation). The EDX analysis of the samples and single crystal was carried out by REMMA-102-02 and Zeiss EVO MA10. The influence of Indium substitution by other p -element on the nature of interaction and solubility type was determined. Solubility ranges for solid solutions were found and changes of unit cell parameters were calculated: TbNiIn 1-0 Al 0-1 (ZrNiAl-type structure, space group P - 62 m , a = 0.7449–0.6997(2), c = 0.378–0.3889(1) nm); TbNiIn 1-0 . 6 Ge 0-0 . 4 (ZrNiAl-type structure, space group P - 62 m , а = 0.7449–0.74348(6), с = 0.378–0.38063(4) nm); TbNiGe 1-0 . 5 In 0-0 . 5 (TiNiSi-type structure, space group Pnma , а = 0.69499–0.69598(7), b = 0.42306–0.42475(4), с = 0.72813–0.72996(7) nm); TbNiSb 1 . 0-0 . 6 In 0-0 . 4 (MgAgAs-type structure, space group F -43 m , a = 0.62662(2)–0.62011(5) nm). The crystal structures of the TbNiIn 0 . 28 Al 0 . 72 compound were investigated by single crystal X-ray analysis (Stoe IPDS II diffractometer, Mo K α-radiation). The refined compositions are confirmed by the results of the EDX analysis (Zeiss EVO MA10 scanning electron microscope). The structures were solved and refined using JANA2006 package: ZrNiAl-type structure, space group P - 62 m, Pearson symbol hP 9, a = 0.71452(6), c = 0.38394(3) nm, R 1 = 0.0152, 307 F 2 values, 15 variables). The formation of solid solutions and the character of the unit cell parameters variation in the studied and related systems briefly discussed. Keywords: indium, solid solution, powder data, single crystal, crystal structure.

Experimental study and thermodynamic re-assessment of the Co–Sb system

The Co–Sb system is of a special attention due to existence of CoSb3 skutterudite structure which is the key structure for doped skutterudite based thermoelectric materials. A critical review of this system, performed recently, shows the published thermodynamic assessment may not be fully correct compared to existing studies. Especially, there is a contradiction in the position of the liquidus line on the Sb-rich side of the phase diagram and of the eutectic reaction, liquid ↔ CoSb3 + (Sb). As these data are crucial for the study of thermal stability of skutterudite based thermoelectric materials, a good knowledge on phase relations in the Sb-rich part of the Co–Sb phase diagram is needed. To obtain reliable data, experimental alloys covering 80 to 100 at.% of Sb were prepared and investigated by differential thermal analysis and phase analysis. The data were compared with existing literature information and thermodynamic re-assessment of this binary system based on the CALPHAD approach was done.

Enthalpies of mixing in ternary Ce–Cu–Sb liquid alloys

Abstract The enthalpies of mixing in liquid alloys of the ternary Ce–Cu–Sb system were determined over a wide range of compositions by means of isoperibolic calorimetry at temperature 1300 K. Measurements were performed along five sections (x Cu/x Sb = 0.20/0.80; 0.40/0.60 and 0.60/0.40 for x Ce changed from 0 up to 0.35 and x Cu/x Ce = 0.20/0.80 and 0.60/0.40 for x Sb changed from 0 up to 0.25). The enthalpies of mixing in the ternary system were found to be exothermic and steadily increasing in absolute values from the binary constituent systems Ce–Cu and Cu–Sb towards the Ce–Sb boundary, reaching the minimum value of approximately –120 kJ · mol–1 in the vicinity of the phase CeSb.

Continuous/reversible phase transition behaviors and their effect on the hysteresis energy loss of the anodes in Na-ion batteries

Alloying anode materials undergo a continuous and reversible phase transition during battery cycles, and the energy consumed during this process determines the energy efficiency of the anode. In this study, using the combined technique of voltammetric experiments and first-principles calculations, comparative studies are performed on P and Sb anodes to identify their phase transition behaviors, associated with the charge–discharge processes of Na-ion batteries (NIBs). To quantitatively establish the phase transition vs energy efficiency relationship of the anode materials of NIBs, we developed a thermodynamic model that replicates the polarization curves observed in voltammetric measurements. We obtained theoretical polarization curves by analyzing the phase transformation sequence and corresponding changes in the resistivity values of intermediate phases of the Na–P and Na–Sb systems under various applied potentials. The formation of various intermediate metastable phases and their high electrical resistivity are identified to be responsible for the increased loss in energy at the anodes. While filling the knowledge gaps on the reasons as to why the Na–P and Na–Sb systems exhibit different hysteresis losses, the outcomes of this study provide a crude yet basic guideline for the appropriate choice of potential anode materials with superior energy efficiencies suitable for NIBs.

On the predictive, quantitative properties of the amphoteric native defect model

The amphoteric native defect model phenomenologically explains and categorizes observed background doping concentrations and accounts for the doping limitations in compound semiconductors. Here, we test and verify the model’s capabilities as a quantitative, predictive tool. We demonstrate that the nature, (donor or acceptor), of non-stoichiometry related vacancy-like defects in the (Al,Ga,In)(As,Sb) system is determined by the position of the intrinsic Fermi energy, EFi at the growth temperature relative to the Fermi level stabilization energy, EFS, a universal energy reference located at 4.9 eV below the vacuum level. We show that a dramatic and predictable conduction type-flip from n- to p-type occurs when EFi is deliberately shifted from below to above EFS.

Unraveling the stacking effect and stability in nanocrystalline antimony through DFT

Two-dimensional nanocrystals with semiconducting electronic properties are emerging as promising materials for electronic devices. Here, we present the density functional theory calculations of structural stability, Raman spectra and electronic properties of monolayer, bilayer (AA and AB stacking) and trilayer (AAA and ABC stacking) antimony (Sb). The cohesive energy and phonon band dispersion results revealed that free-standing Sb systems are stable materials. Calculated Raman spectra showed distinct active modes, thus facilitating the characterisation of multilayered structures in different stacking arrangements. It was found that high-frequency in-plane (Eg) and out-of-plane (A1g) modes can shift as much as 16 cm−1 and 28 cm−1 as the layer number increases from monolayer to trilayer. Band structure calculations showed that monolayer and bilayer (AA stacked) Sb are semiconductors with band gap values 1.26 eV and 0.55 eV, respectively, whereas bilayer (AB) and trilayer Sb displayed metallic character. Spin-orbit coupling interaction was also incorporated in band structure calculations and was found to reduce the band gap of monolayer Sb to 1.0 eV while it does not effect on the band gap values of other systems. Moreover, it was seen that nanocrystalline Sb exhibit isotropic mechanical properties. The carrier mobility calculations showed that electron/hole mobility increases by 5/32 times from monolayer to trilayer, respectively.

In situ scanning tunneling microscopy study of bipyridine adsorption at semi-metallic Sb(111) plane

The adsorption characteristics and organic adlayer formation properties of bipyridine molecules at semi-metallic Sb(111) electrodes in an aqueous electrolyte solution are studied by means of in situ scanning tunnelling microscopy (STM), cyclic voltammetry and electrochemical impedance spectroscopy. The capacitance–potential response shows a small capacitance hump for 4,4′-bipyridine (BP) adsorption at the Sb(111) interface, the position of which is slightly dependent on the electrolyte pH. No such capacitance vs. potential curve feature was observed for the adsorption of 2,2′-BP at Sb(111). STM measurements show a clean initial surface structure for the 4,4′-BP system and a higher level of noise interference in the case of the 2,2′-BP│Sb(111) system. The atomic resolution of the Sb(111) structure can be measured for both 2,2′-BP and 4,4′-BP additives and the formation of adsorbed molecular rows can be observed for the 4,4′-BP additive at the Sb(111) surface. The surface coverage of the molecules and the gaps between them suggest that 4,4′-BP is adsorbed in bi-protonated form with solvated anions stabilizing the adlayer structure. The reduction of BP molecules starts negative polarization and is significantly both pH- and potential-dependent. The formation of non-structured deposits is seen as a result of this process, which is deemed to be irreversible.

Interaction of the Components in the {Ce, Gd}-{Ti, Zr}-Sb Systems

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.