Excess Of Indium Research Articles

Investigation of the physico-chemical properties of In2S3 powder synthesized via solid-state reaction and In2S3 thin films prepared through thermal evaporation

In this study, we examined the physico-chemical properties of In2S3 powder produced using the solid-state reaction and of the In2S3 thin film obtained using the thermal evaporation technique. Thermally evaporated In2S3 thin films were subjected to vacuum annealing to study the impact of heating on the structural, morphological and optical properties of the samples. According to the X-ray diffraction analysis, the microstructure of as-grown thin films were an amorphous in nature which transformed into polycrystalline structure after annealing at T≥250 °C. This polycrystalline structure suggests the formation of the β-In2S3 phase with a tetragonal and/or cubic crystal structure. In addition, the energy dispersive spectroscopy analysis revealed that all samples show a slight excess of indium and a deficit of sulfur, compared to the stoichiometric ratios. Moreover, surface micrographs recorded by atomic force microscopy showed an increase in surface roughness after annealing. Optically, the transmittance spectra, T(λ), illustrated a high transmittance average value,∼70 %, while the reflectance spectra, R(λ), showed an average value of 25 % in the visible and NIR region. It appeared that heat treatment had no significant impact on the T and R spectra. The optical dispersion parameters of the treated samples were also studied. The direct and indirect allowed bandgap transitions values of all samples were found to ranging from 1.75 to 2.48 eV and from 1.80 to 2.38 eV, respectively. Such observation shows that the bandgap increased with annealing temperature. Electrically, n-type conductivity for In2S3 films annealed at 250 °C was recorded.

A Micro-Reference Electrode for Electrode-Resolved Impedance and Potential Measurements in All-Solid-State Battery Pouch Cells and Its Application to the Study of Indium-Lithium Anodes

Impedance measurements are a powerful tool to investigate interfaces in lithium-ion batteries (LIBs). In order to deconvolute the anode and cathode contributions to the cell impedance, a reference electrode (RE) is required. However, there are only very few reports on the use of a three-electrode setup with an RE for all-solid-state batteries (ASSBs), which is due to the complexity of integrating an RE with a suitable geometry into the typical ASSB test cells that are based on a compressed electrolyte pellet. In this study, we present a straightforward approach to implement a micro-reference electrode (μ-RE) for electrode-resolved impedance and potential measurements into ASSB pouch cells. The μ-RE consists of an insulated ∼64 μm diameter gold wire that is sandwiched between two Li6PS5Cl/polymer separator sheets and activated by in situ electrochemical lithiation. Using this μ-RE, we investigate the electrode potential and the accessibility of cyclable lithium at the separator interface of indium-lithium anodes, which are prepared by stacking lithium and indium foils with a molar excess of indium. We compare two different cell assembly configurations, with the separator faced by either (i) the formerly In-side or (ii) the formerly Li-side, showing that only the latter case provides a reservoir of cyclable lithium.

Continuous Flow Aqueous Synthesis of Highly Luminescent AgInS2 and AgInS2/ZnS Quantum Dots

Continuous flow synthesis of semiconductor quantum dots (QDs) holds the promise of being highly reproducible, being scalable, and providing precise control of all reaction parameters. Here, we applied this technique to the aqueous synthesis of the Ag–In–S (AIS) core and AIS/ZnS core/shell QDs and optimized several parameters comprising reaction temperature, pressure, time, nature, and the ratio of precursors. Photoluminescence quantum yield (PLQY) values of 32%/44% (average/best) for the core and 77%/83% for the core/shell system have been obtained in short reaction times (8–15 min). We demonstrate by means of combined structural and optical studies that the high PLQY originates from donor–acceptor pair recombination processes, involving essentially [InAg2+ + 2VAg–] defect complexes whose formation is favored by the large excess of indium used (In:Ag ratio of 4:1), and the low reaction temperature (100–120 °C). The structural disorder is further enhanced during ZnS shell growth, which in addition to surface passivation and removal of nonradiative decay channels leads to the partial diffusion of the added zinc ions into the AIS core and the formation of ZnIn− antisite defects. The presented method provides excellent reproducibility and high scalability, facilitating the large-scale production of highly luminescent AIS/ZnS QDs.

Synthesis of In–In2O3 microstructures by close-spaced vapor transport (CSVT) and their transformation to In2O3 nanobelts at low temperature

Indium oxide (In2O3) microstructures were synthesized through carbothermal reaction by the close-spaced vapor transport (CSVT) technique at low temperatures and without the use of catalysts. Morphological characterization by scanning electron microscopy (SEM) showed that the CSVT technique provides high-efficiency for the mass transport at low temperatures, as low as 650 °C, considering that in the synthesis indium oxide powders were used as a source. In addition, it is observed that the microstructures are formed mainly of microcubes with microspheres attached on their faces. Measurements of X-ray (XRD), Raman, and Energy-dispersive X-ray spectroscopy (EDS) showed that the microcubes tend to the stoichiometry of In2O3 and the microspheres have an excess of indium. Based on the above results, the microstructures were converted to In2O3 nanobelts by a simple post thermal annealing for 16 h in a nitrogen environment, according to additional morphological and structural characterizations. The results revealed that the In2O3 nanobelts have several micrometers in length with rectangular cross sections in the range from 50 to 250 nm and correspond to body-centered cubic (bcc) In2O3 single crystal. The growth mechanisms of the microstructures and nanobelts are discussed in detail. Finally, Photoluminescence spectrum showed a broad emission around 600 nm. Refined studies showed three peaks at 420, 592, and 673 nm, which were attributed to oxygen vacancies.

Characterization of dispersed indium species obtained by thermal treatment of In–NH 4-zeolites and their impact on the SCR of NO x

Indium species dispersed on zeolites by high temperature treatment in air of indium-impregnated NH 4-zeolites were characterized and related to the catalytic behavior of the solids in the selective catalytic reduction of NO x . NO-TPD, H 2-TPR and CO-TPR experimental results show that higher temperatures increase the fraction of dispersed InO + and In x O y phases. These species can oxidize nitric oxide to NO 2 and are in greater amounts on the mordenite framework. X-ray indium mapping and TEM observations show a heterogeneous distribution of In 2O 3 particles in solids with higher indium content. These oxides have smaller crystal size and a larger interaction in the framework of ZSM5. TGA–SDTA results point out that the thermal treatment simultaneously produces a solid-state indium exchange and a zeolite dehydroxylation, the exchange level being higher at larger indium contents. The catalytic behavior of the In–zeolites studied can be explained in terms of the type and proportion of indium species present according to the indium loading, thermal treatment and type of zeolite framework. For both zeolites, a higher temperature treatment extends the NO x conversion windows because there are larger amounts of active InO +. But the maximum deNO x activity is lower for In–mordenite due to the larger amounts of In x O y in this zeolite. This non-selective phase increases the methane conversion level. When the indium content is higher, the deNO x activity further increases, in line with a larger fraction of active InO + species. Besides, the catalytic activity of the solids does not decrease despite the excess of indium in these samples under the form of In 2O 3 crystals.

Synthesis of n-type CuInS2 Particles Using N-methylimidazole, Characterization and Growth Mechanism

We report on the growth of CuInS2 n-type semiconductive particles, prepared using N-methylimidazole, as a solvent and/or a complexing agent, as well as their chemical and electrochemical properties. XPS, EDX and ICP-AES have shown that an excess of indium was obtained, which was greater at the surface (CuIn1.19S1.7 at 500 °C) than in the bulk (CuIn1.07S1.9 at 500 °C). Solid state Raman spectroscopy revealed two crystalline phases: chalcopyrite and the so-called copper−gold phase, and by increasing the annealing temperature of the particles, the formation of the chalcopyrite phase is favored. UV−visible measurements showed that the n-type CuInS2 possesses a direct bandgap energy of 1.55 eV. To perform the capacitance measurements on a CuInS2 film by EIS, we used two organic redox couples in nonaqueous media: 5-mercapto-1-methyltetrazolate (T−)/di-5-(1-methyltetrazole) disulfide (T2), and 5-trifluoromethyl-2-mercapto-1,3,4-thiadiazolate (G−)/5,5′-bis(2-trifluoromethyl-1,3,4-thiadiazole) disulfide (G2). Usin...

Speciation of chloroindate(iii) ionic liquids

A range of chloroindate(iii) ionic liquid systems was prepared by mixing of 1-alkyl-3-methylimidazolium chloride with indium(iii) chloride in various ratios, expressed as the mol fraction of indium(iii) chloride, chi(InCl(3)). For chi(InCl(3))</= 0.50, the products were liquids, whereas for chi(InCl(3)) > 0.50, the products were biphasic (suspensions of a solid in an ionic liquid). Speciation of these chloroindate(iii) systems was carried out using a wide range of techniques: differential scanning calorimetry (DSC), polarised optical microscopy (POM), liquid-state and solid-state (115)In NMR spectroscopy, X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). Ionic liquids prepared using an excess of the organic chloride (chi(InCl(3)) < 0.5) contained [InCl(6)](3-), [InCl(5)](2-) and [InCl(4)](-) anions, in proportions dependent on the chi(InCl(3)) value. Equimolar mixtures yielded single compounds: 1-alkyl-3-methylimidazolium tetrachloroindates(iii). Systems containing an excess of indium(iii) chloride (chi(InCl(3)) > 0.5) contained indium(iii) chloride powder suspended in a neutral tetrachloroindate ionic liquid.

Synthesis, Characterization, and Growth Mechanism of n-Type CuInS2 Colloidal Particles

We report on the growth of CuInS2 n-type semiconductive particles, prepared using a modified Czekelius’s colloidal method, as well as their chemical and electrochemical properties. Solid state Raman spectroscopy revealed two crystalline phases: chalcopyrite and the so-called copper−gold phase. Increasing the annealing temperature of the particles favors the formation of the chalcopyrite phase. As shown by XPS, EDX, and ICP-AES, an excess of indium was obtained, which was greater at the surface (CuIn1.45S1.9 at 450 °C) than in the bulk (CuIn1.04S1.74 at 450 °C). UV−visible measurements showed that the n-type CuInS2 possesses a direct bandgap energy of 1.45 eV. Two organic redox couples in nonaqueous media were used to perform the capacitance measurements carried out by EIS on a CuInS2 film: 5-mercapto-1-methyltetrazolate (T−)/di-5-(1-methyltetrazole) disulfide (T2) and 5-trifluoromethyl-2-mercapto-1,3,4-thiadiazolate (G−)/5,5′-bis(2-trifluoromethyl-1,3,4-thiadiazole) disulfide (G2). Fermi levels of −3.95 e...

Selective Second Order Derivative Spectrophotometric Method for the Determination of Gallium(III) in Presence of Large Excess of Indium(III)

A simple, sensitive, and selective second order derivative spectrophotometric method is proposed for the determination of microgram quantities of gallium(III) especially in presence of large excess of indium(III). Ga(III) reacts with 2‐hydroxy‐3‐methoxy benzaldehyde isonicotinoylhydrazone (HMBAINH) chromogene forming an intense greenish yellow coloured soluble complex in acidic buffers and in presence of 0.2% of triton X‐100. The complex showed maximum absorption at 405 nm and at pH 5.0, where the reagent has negligible absorbance. A second order derivative spectrum of the complex solution showed maximum derivative amplitude at 415 nm and again at 460 nm with a zero cross at 442 nm. Beer's law was obeyed in the concentration range 0.036–1.533 µg/ml and 0.070–1.533 µg/ml of Ga(III) at 415 nm and 460 nm, respectively. However, at 404 nm In(III)‐HMBAINH complex showed zero amplitude in the second order derivative spectrum where Ga(III)‐HMBAINH obeyed Beer's law in the range of 0.070–1.394 µg/ml. This allows determination of Ga(III) in presence of large excess of In(III) by second order derivative spectrophotometry. The tolerance limits of other diverse ions and other analytical parameters were also evaluated. The method was applied for the determination of gallium in some synthetic mixtures containing indium.

Crystal Growth, Structural, and Property Studies on a Family of Ternary Rare-Earth Phases RE2InGe2 (RE = Sm, Gd, Tb, Dy, Ho, Yb)

A series of new rare-earth indium−germanides RE2InGe2 (RE = Sm, Gd, Tb, Dy, Ho, Yb) have been prepared from the corresponding elements through high-temperature reactions using an excess of indium as flux. Single-crystal and powder X-ray diffraction studies showed that these ternary phases crystallize in the tetragonal space group P4/mbm, Z = 2, Pearson's symbol tP10, and represent new members of the Mo2FeB2 family (an ordered ternary variant of the U3Si2 structure type). The temperature dependence of the dc magnetization (5−300 K) indicates that the RE2InGe2 (RE = Sm−Ho) compounds order magnetically below ca. 60 K, whereas Yb2InGe2 exhibits Pauli-like temperature-independent paramagnetism. Isothermal magnetization, electrical resistivity, and calorimetry measurements are presented as well and confirm the existence of ordered antiferromagnetic states at low temperatures. The structural trends and the evolution of the magnetic properties are also discussed.

Ternary Indides RE4Pd10In21 (RE = La, Ce, Pr, Nd, Sm) — Synthesis, Structure, and Physical Properties

AbstractThe ternary indium compounds RE4Pd10In21 (RE = La, Ce, Pr, Nd, Sm) were synthesized from the elements in glassy carbon crucibles in a high‐frequency furnace. Single crystals of Sm4Pd10In21 were obtained from an indium flux. An arc‐melted precursor alloy of the starting composition ∼SmPd3In6 was annealed with a slight excess of indium at 1200 K followed by slow cooling (5 K/h) to 870 K. All compounds were investigated by X‐ray powder diffraction and the structures were refined from single crystal diffractometer data. The RE4Pd10In21 indides are isotypic with Ho4Ni10Ga21, space group C2/m: a = 2314.3(2), b = 454.70(7), c = 1940.7(2) pm, β = 133.43(2)°, wR2 = 0.0681, 1678 F2 values for La4Pd10In21, a = 2308.2(1), b = 452.52(4), c = 1944.80(9) pm, β = 133.40(1)°, wR2 = 0.0659, 1684 F2 values for Ce4Pd10In21, a = 2303.8(2), b = 450.78(4), c = 1940.6(1) pm, β = 133.39(1)°, wR2 = 0.0513, 1648 F2 values for Pr4Pd10In21, a = 2300.2(2), b = 449.75(6), c = 1937.8(2) pm, β = 133.32(1)°, wR2 = 0.1086, 1506 F2 values for Nd4Pd10In21, and a = 2295.6(2), b = 447.07(4), c = 1935.7(1) pm, β = 133.16(1)°, wR2 = 0.2291, 2350 F2 values for Sm4Pd10In21, with 108 variables per refinement. All palladium atoms have a trigonal prismatic coordination. The strongest bonding interactions occur for the Pd—In and In—In contacts. The structures are composed of covalently bonded three‐dimensional [Pd10In21] networks in which the rare earth metal atoms fill distorted pentagonal channels. The crystal chemistry and chemical bonding in these indides is briefly discussed. Magnetic susceptibility measurements show diamagnetism for La4Pd10In21 and Curie‐Weiss paramagnetism for Ce4Pd10In21, Pr4Pd10In21, and Nd4Pd10In21. The neodymium compound orders antiferromagnetically at TN = 4.5(2) K and undergoes a metamagnetic transition at a critical field of 1.5(2) T. All the RE4Pd10In21 indides studied are metallic conductors.

The Surface Tension of Melts of Aluminum–Indium Binary System

The temperature and concentration dependences of the surface tension (ST) of alloys of the Al–In system are investigated by the sessile drop method. It is shown that small (up to 0.6 at. %) additions of indium significantly lower the ST of aluminum, and the temperature coefficients of ST of the investigated alloys have positive values in this range of compositions. The obtained data are used to calculate the adsorption of indium (according to Guggenheim–Adam, N option) and the number of its monolayers (according to Rusanov) in the surface layer of Al–In solutions. It follows from these data that the adsorption of indium on the melt surface reaches the maximal value with a bulk content of indium of about 0.1 at. %, and the excess of indium in the surface layer corresponds to three monolayers of indium.

Synthesis, Structure, and Magnetic Properties of CeNiIn2

Single crystals of the ternary indide CeNiIn2 were synthesized from an indium flux. An arc-melted button of the starting composition CeNiIn2 was annealed in a zirconia crucible with a slight excess of indium at 1200 K followed by slow cooling (5 K/h) to 870 K. The new indide has been investigated by X-ray diffraction on powders and single crystals: PrNiIn2 type, Cmcm, a = 440.78(4), b = 1834.3(1), c = 2178.8(2) pm, wR2= 0.0753 for 1471 F2 values and 66 variable parameters. The structure contains three crystallographically independent nickel positions which have a distorted trigonal prismatic coordination. The CeNiIn2 structure is related to the MgCuAl2 structure by chemical twinning. The shortest interatomic distances occur for Ni-In and In-In contacts. The nickel and indium atoms form a complex three-dimensional [NiIn2] network in which the cerium atoms fill distorted pentagonal channels. Magnetic susceptibility measurements indicate Curie-Weiss behavior with an experimental magnetic moment of 2.44(3) μB/Ce atom. At 3.4(3) K CeNiIn2 orders ferro- or ferrimagnetically. The experimental saturation magnetization at 2K and 5.5 T is 0.95(2) μB/Ce.

Microgravity Solidification of Immiscible Alloys

AbstractThis paper covers findings obtained from the microgravity directional solidification of immiscible aluminum-indium alloys during the Life and Microgravity Spacelab Mission in 1996. Three alloys, one of monotectic composition and two alloys containing an excess of indium above the monotectic (i.e., hypermonotectic compositions) were solidified using the Advanced Gradient Heating Facility (AGHF). Samples were processed in specialized ampoule assemblies containing pistons and a high temperature spring in a partially successful attempt to prevent void formation due to thermal contraction of the melt and solidification shrinkage. A comparison of compositional variations between microgravity processed and ground processed samples revealed compositional variations along the length of ground processed samples which were representative of results anticipated due to convective mixing in the melt. Flight samples showed an initial compositional variation indicative of minimal mixing in the melt. However, a discontinuity in the microstructure was observed which coincided with the presence of a void in the flight sample.

Determination of cadmium in indium phosphide by electrothermal atomic absorption spectrometry and ion-selective electrode potentiometry

Two independent methods for the determination of cadmium in cadmium-doped indium phosphide have been developed. Electrothermal atomic absorption spectrometry (ETAAS) utilized both platform atomization and a chemical modifier composed of magnesium nitrate and orthophosphoric acid. As the matrix mass was found to influence the cadmium sensitivity, matrix matched calibration standards were necessary. The detection limit (3sB) is 0.20 μg/g for a 100 mg sample. The electrochemical method employed a solid-state cadmium sulfide-silver sulfide electrode as potentiometric sensor. An excess of indium (III) influenced the electrode response. A preliminary chelation-extraction of indium with acetylacetone at pH 5.0 in acetate buffer overcame the interference. The detection limit of the ISE-potentiometric method is 10 μg/g for a 200 mg sample. Two indium phosphide single crystals grown from melts doped with cadmium sulfide or cadmium telluride were analyzed for their cadmium content.

Oxidation of In‐48Sn

The oxidation of In‐48Sn was investigated at partial pressures between 10−8 and 10+4 Pa over the temperature range from 22 to 250°C with different analytical methods. The oxide film contains a mixture of several oxides, although indium oxide forms preferentially. The measurements show at the surface an excess of indium compared to the eutectic composition. Below the melting point, a logarithmic growth, and above this point, a parabolic growth of the oxide film was observed. The oxide film formed in air at 250°C does not exceed about 50 nm in the first 5 min of oxidation.

Determination of chloride at picogram levels by molecular fluorescence in a graphite furnace

Chloride was determined at nanogram levels by adding excess of indium to the sample introduced into a graphite furnace and measuring the laser induced molecular fluorescence of indium chloride. The diatomic molecules of indium chloride were excited by a pulsed dye laser at 267 nm and fluorescence was measured at 359 nm. The effects of various parameters including amount of indium added, furnace thermal conditions and presence of concomitants were also studied. A linear calibration in the range of 0.025-1.25 ng and a detection limit of 17 pg of chloride were obtained under optimum conditions. The analytical usefulness of the method was checked by determining the chloride content in National Institute of Standards and Technology, Standard Reference Materials 1571a and 1571b Orchard Leaves.

Development of solar cell material by PAC:111In probes in CuInS2 and related phases

Using metallic indium doped with radioactive111In as one of the starting materials samples of stoichiometric CuInS2, CuInS2 with excess of indium and sulphur, and stoichiometric CuIn5S8 were prepared. Perturbed angular correlations of γ rays emitted by111Cd are utilized to analyse the produced crystalline phases.

Growth and characterization of CuInSe 2 films by close-space evaporation

CuInSe 2 thin films were prepared on mica substrates using an evaporation technique which involved varying the distance between the source and the substrate. Films evaporated on substrates at distances less than 1 cm from the source exhibited preferential orientation in the (112) direction. The grain size increased from 0.5 to 1.0 μ m as the source substrate distance decreased from 3 to 1 cm. The conductivity increased with a decrease in the distance between the source and substrate. Electron probe microanalysis of these films showed that films coated on substrates farther away from the source had a slight selenium deficiency and an excess of indium. Three characteristic energy gaps of 1.01, 1.25 and 2.4 eV were obtained from an analysis of the optical absorption spectrum. The optical transition probability for valence band to conduction band transitions was estimated to be 10.91 eV which gives an admixture of copper d states to the valence band of 32%.

Preparation and characterization of vacuum deposited CuInSe 2 thin films

CuInSe 2 is a promising material for photovoltaic solar cells. Thin films of CuInSe 2 were prepared by vacuum evaporation of the constituent elements by the “three-temperature” method. Source temperatures rather than the elementary fluxes were controlled. The deposition set-up configuration permitted the simultaneous preparation of films with compositions varying around exact stoichiometry. CuInSe 2 thin films with indium concentrations of ±3 at.% around stoichiometry had predominantly chalcopyrite structure with {112} crystallographic texture. These films were p-type, with resistivities of 2 × 10 −2 − 27 Ω cm , carrier concentrations of 1 × 10 18 − 4 × 10 20 cm −3 and Hall mobilities of 0.2 – 2 cm 2 V −1 s −1. Films with about 5 at.% excess of indium showed mostly the sphalerite phase with {111} texture and a small proportion of the chalcopyrite phase. These films exhibited resistivities in the range 2 − 9 × 10 3 Ω cm . The films with about 5 at.% excess of copper consisted of berzelianite and/or sphalerite phases. The band gaps of nearly stoichiometric CuInSe 2 thin films and those with 5 at.% excess of indium ranged from 0.99 to 1.01 eV.