Indium Salt Research Articles

One-Step Transformation of Aryl Diazonium Salts into Aryl Indium(III) Reagents.

A method for the conversion of diazonium salts into intrinsically nucleophilic aryl indium reagents is described. The reaction is performed using indium(I) bromide with the C-In bond being formed by the interaction of aryl radicals with the indium salt. The obtained aryl indium(III) reagents work well in the Liebeskind-Srogl cross-coupling with thioesters, affording a wide variety of aryl ketones. This two-step transformation is a general method for the acylation of diazonium salts.

Unique Porous Structures Supported by Anodic Treatments in Liquid Ammonia (-50°C, Patm)

Since the first anodic porosification of semiconductors in the 1950s, numerous studies have reported a wide range of porous structures. The conditions used during the growth of pores can explained the shapes obtained but the formation mechanism and especially the influence of surface chemistry during porosification still raise many questions.It is in such context that the contribution of liquid ammonia (-55°C) is crucial. Indeed, this remarkable non-aqueous solvent allows, on the one hand, to obtain novel porous structures on n-InP and, on the other hand, it allows for the first time a specific and original interfacial chemistry, governed by the chemistry of nitrogen.In fact, in liquid ammonia, the dissolution of III-V semiconductors (GaAs, InP) is systematically done after a surface passivation step. This passivation step is particularly stable on InP and revealed the formation of a phosphazene type film (monolayer) resulting from the concomitant oxidation of the solvent and the semiconductor. The "multi-material" approach is a key factor, as it underlines the determinant role of the surface chemistry. In fact, at higher current densities, the porous structures of n-InP and n-GaAs show contrasting structures, which give an original behaviour compared to the aqueous medium. In order to determine the efficiency of the dissolution mechanism (at lower and higher current density), the quantity of indium (or gallium) salt will be quantified by Inductively coupled plasma optical emission spectroscopy analysis after ammonia evaporation.Moreover, the remarkable reproducibility of the anodic behaviour allowed physico-chemical characterisations of the porous surface, supported by scanning electron microscopy and the variation of the interfacial potential, photoluminescence and X-ray photoelectron spectroscopy.More specifically on n-InP, where an original structure was revealed, these analyses, during the early stages of porosification, led to the identification of a porosification mechanism in this solvent. Furthermore, at higher current densities, an amorphous film becomes thicker on the surface of the porous structure. Further porosification requires the permeability of this amorphous structure which would most probably result from the polymerisation of phosphazene since the presence of nitrogen could be clearly identified on the pore walls by Auger spectroscopy.

Indium-Catalyzed C-F Bond Transformation through Oxymetalation/β-Fluorine Elimination to Access Fluorinated Isocoumarins.

Fluorinated heterocycles have attracted much attention in the pharmaceutical and agrochemical industries. Many strategies have already been developed to achieve the synthesis of fluorinated heterocycles. Formidable challenges remain, however, in the synthesis of fluorinated isocoumarin derivatives that are among the most alluring structural motifs. Herein, the indium-catalyzed C-F bond transformation of 2-(2,2-difluorovinyl) benzoates is reported, which are readily accessible compounds, to give a diverse array of fluorinated isocoumarins. The present reaction proceeds smoothly using inexpensive reagents: a catalytic amount of indium salt in the presence of zinc salt. A theoretical calculation of potential energy profiles showed that the reaction consists of oxymetalation with the elimination of alkyl halide and the β-fluorine elimination.

Aqueous spray pyrolysis of CuInSe2 thin films: Study of different indium salts in precursor solution on physical and electrical properties of sprayed thin films

Herein, we deposited CuInSe2(CISe) thin films by using aqueous spray deposition method and post selenization process. The effect of different indium precursor salts including indium chloride, indium nitrate and indium acetate on the structural, morphological, optical and electrical properties of sprayed CISe layers has been studied by using x-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM-EDS), optical transmission (UV–Vis), Mott-Schottky analysis, I–V dark measurements. Although all the deposited thin films show a chalcopyrite tetragonal ordering structure of CISe, the crystallinity, morphology, and electrical characteristics are strongly influenced by the type of indium salt. A highly compact film with large grains (500–1000 nm) can be obtained after selenization of deposited film from indium chloride precursor while indium nitrate precursor results in low grains size and indium acetate precursor leads to rough surfaces with very small grain size. According to Mott-Schottky results, all films are p-type with carrier concentration in the range of ~1017 cm−3 to ~1019 cm−3 and the smallest value of 2.8 × 1017 cm−3 is obtained for CISe film deposited from indium nitrate precursor. The XRD and J-V dark results revealed that the CISe films deposited from indium chloride precursor demonstrates better crystallinity and higher mobility relative to other precursors.

Investigation of precursors concentration in spray solution on the optoelectronic properties of CuInSe2 thin films deposited by spray pyrolysis method

Copper indium selenide CuInSe2(CISe) thin films were deposited by chemical spray pyrolysis (CSP) method of CuInS2(CIS) and subsequent selenization process. To study the effects of solution concentration, we prepared different precursors solution of CIS including different amount of indium salts from 0.025 to 0.100 M with In/Cu 1.25 and S/In 4. These results propose that solution concentration is critical for inflecting the morphological, optical, electrical, and electrochemical characteristics of solution-processed CISe films and device performance. The studied morphological properties of deposited samples were homogenous, crack-free with large grains in indium salt concentrations more than 0.075 M. The deposited film thickness depends on the spray precursor concentration and increases for higher concentration. In addition with increasing of indium precursor concentration from 0.025 to 0.100 M in spray solution, the optical bandgap of deposited film decreases from 1.40 to 1.35 eV. Also the films mobility and carrier density were notably influenced by any change in the solution concentration. Electrical and electrochemical properties showed a decrease in carrier density from ~ 1020 to ~ 1017 cm−3 and the increase in mobility of order ~ 10–7 to ~ 10–2 cm2/V s, respectively, for 0.025 M, 0.100 M CISe films. All films exhibited p-type conductivity owing to different concentrations. However, it seems that the concentration of the ideal solution is 0.100 molars.

Room-temperature preparation of MIL-68 and its derivative In2S3 for enhanced photocatalytic Cr(VI) reduction and organic pollutant degradation under visible light

Abstract MIL-68, a typical In-based MOF, has been studied in many fields due to its excellent performance. Facile preparation of MIL-68, suitable for scalable preparation and industrial applications, is of great significance. In this work, a method for the room-temperature preparation of rod-like MIL-68 at the nano- and micro-scales was developed for the first time, in which water or salts such as NaF, sodium formate, sodium acetate and sodium propionate were used as modulating reagents. It appears that these modulating reagents can promote the deprotonation of terephthalic acid and the hydrolysis of indium salt to accelerate crystal nucleation. The size of MIL-68 can be controlled by changing the modulating reagents. Hollow porous In2S3 particles composed of assembled ultrathin nanosheets were obtained via sulfidation treatment using MIL-68 as a self-sacrifice template, and the obtained In2S3 exhibited excellent photocatalytic activity toward Cr(VI) reduction and methyl orange degradation under LED visible light irradiation. Furthermore, the photocatalytic mechanism and reusability were studied.

Study on spray-pyrolyzed In2S3 thin films, targeted as electron transport layer in solar energy

Efficient electron transport layers (ETLs) play a pivotal role in the performance of solar cells. In recent years, Indium sulfide (In2S3) has been studied as a promising ETL in CuInGaS(e)2, Cu2ZnSnS(e)4, and perovskite solar cells. Despite several studies on spray-deposited In2S3, there is no complete experimental investigation on In2S3 thin films. The effect of the molar ratio of S/In and the type of indium precursor on the structural, morphological, optical, and electrical properties of sprayed-In2S3 layers has been studied. Films were characterized using x-ray diffraction, scanning electron microscopy (SEM), optical transmission (UV-Vis), Mott–Schottky analysis, four-point probe, and cyclic voltammetry measurements. The crystallinity and morphological characteristics are strongly influenced by the type of indium salt, where indium acetate precursor results in a highly porous film compared with nitrate and chloride precursors. The chloride precursor demonstrates better crystallinity and considerably lower sheet resistance. All films are n-type with a carrier concentration in the range of ∼2 × 1017 to ∼2 × 1018 cm − 3, with an indirect bandgap of 2.0 eV.

Effect of the Deposition Conditions on the Anion Resin Exchange Precipitation of Indium(III) Hydroxide

A new patented method for the synthesis of nanosized powders of indium(III) hydroxide and oxide using the strong base anion exchange resin AV-17-8 as a precipitate agent was proposed. The effect of anions of the initial indium salt and the influence of the process duration, temperature, and counterions of resin such as hydroxide or carbonate on the yield of indium(III) hydroxide during the anion resin exchange precipitation were investigated by scanning electron microscopy, electrical conductivity measurement method, and atomic absorption analysis. Based on the obtained data, the mechanism of the anion resin exchange precipitation of indium(III) hydroxide was suggested. The products were characterized by X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, elemental analysis, Brunauer–Emmett–Teller, and transmission electron microscopy. It was found that impurity-free monophasic In2O3 powders with an average particle size of 10–15 nm and specific surface area of 62–73 m2/g were formed after heat treatment of as-prepared products at 400 °C.

High quantum yield pure blue emission and fast proton conduction from an indium-metal-organic framework.

A multifunctional material, with two or more types of functionalities in a single material, might give new phenomena and novel applications. Metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) can be utilized as a highly versatile and tunable platform for exploring multifunctional materials. In this study, an extra thermally stable indium-MOF (1) was synthesized via self-assembly of 1,1'-ethynebenzene-3,3',5,5'-tetracarboxylic acid (H4EBTC) with an indium salt under solvothermal conditions. MOF 1 crystallizes in a tetragonal space group P4/mmm and shows a three-dimensional (3D) anionic framework with one-dimensional (1D) channels along the c-axis direction, and charge-balancing [(CH3)2NH2]+ cations together with lattice DMF and water molecules are accommodated in channels. This multifunctional MOF emits pure blue luminescence under ambient conditions, arising from the π* →π electron transition in EBTC4-, with CIE coordinates of (0.16, 0.07), and shows the highest quantum yield of 61.4% among indium-MOFs. Alternatively, 1 features fast proton conductivity with σ = 3.49 × 10-3 S cm-1 at 25 °C and 99% RH, attributed to the efficiently synergistic proton transfer in the H-bond networks constructed by [NH2(CH3)2]+ cations, lattice water molecules in channels and carboxylate groups in the framework. The notable level of performance of 1, combined with good hydrolytic and extra thermal stability, offers great opportunities for its future applications, and it may behave as a kind of promising multifunctional MOF material.

Quality Control of a Functionalized Polymer Catalyst by Energy Dispersive X-ray Spectrometry (EDX or EDS)

Energy dispersive X-ray spectrometry (EDX or EDS) is a technique often implemented on scanning electron microscopes and a regularly used method for qualitative characterization of solid catalysts. This Technical Note reports a method for the determination of the metal content in a sulfonated polyether ether ketone in the form of an indium(III) salt. The possibility of quantitative determination of the sulfur/indium ratio by EDX was assessed by calibration with two indium salts (sulfide and sulfate) readily available in good purity. The accuracy of the uncorrected instrument response was better than 1% under our conditions. A protocol for investigating the metal content of the solid catalyst is proposed, also providing information about the homogeneity of the metal distribution. Because of the simplicity of the sample preparation, the small quantity of material needed, and the rapidity of the EDX measurements, the method appears to be promising for quantitative characterization of solid catalysts.

The Kinetics of Indium Electroreduction from Chloride Solutions

The electroreduction of indium on indium electrode (99.98%) in perchlorate-containing chloride electrolytes is studied by the methods of linear sweep and cyclic voltammetry, impedance spectroscopy, and chronoamperometry. The indium electroreduction is limited by diffusion, the reaction rate constant is 1.3 10–4 cm/s at the indium salt concentration of 0.1 M. The values of the apparent rate constant for the charge transfer stage found by linear sweep and cyclic voltammetry and also by impedance spectroscopy are 2.37 × 10–3, 3.62 × 10–3, 3.06 × 10–3 cm/s, respectively. The values of diffusion coefficient of indium(III) ions calculated according to the Cottrell equation based on chronoamperametric measurements and from the Warburg impedance found by impedance spectroscopy are in good agreement. The presence of the Gerischer impedance is stated, which suggests that a homogeneous reaction of formation of indium chloride complexes proceeds and its mechanism is chemical-electrochemical.

Porous indium oxide hollow spheres (PIOHS) for asymmetric electrochemical supercapacitor with excellent cycling stability

Porous indium oxide hollow spheres (PIOHS) of 1–2 μm in diameter were synthesized using a cost-effective hydrothermal method followed by the calcination. First, solid carbon-In2O3 composite sphere was formed using indium salt and glucose as indium and carbon precursor, respectively. Porous and hollow structure of pure indium oxide was formed after the successful removal of carbon that acted as a sacrificial template during the high-temperature calcination. Various characterization tools such as electron microscopy, Raman spectroscopy, and electrochemical techniques were used to characterize the synthesized PIOHS. From BET measurements, the specific surface area was estimated as 128 m2 g−1 and the electrode made of PIOHS showed maximum specific capacitance of 320 F g-1 at 1 A g−1 current density during electrochemical studies. This material exhibited 56% rate capability at 10 A g−1 with 86% cycling stability after 3500 cycles at 5 A g−1. The full cell asymmetric supercapacitor was demonstrated with PIOHS as a cathode with a specific capacitance, energy density and power density of 30.84 F g−1, 10.96 W h kg-1 and 80 W kg−1, respectively at 0.1 A g−1 current density along with the specific capacitance retention of 97.1% after 1000 cycles at 1 A g−1 current density. The excellent electrochemical performance of the fabricated full-cell device is mainly attributed to the high surface area, unique three-dimensional porous hollow architecture and better charge transfer kinetics of PIOHS.

Tapping the potential of trioctylphosphine (TOP) in the realization of highly luminescent blue-emitting colloidal indium phosphide (InP) quantum dots

In this work, extremely small blue emitting colloidal InP-based quantum dots (size ~ 2–5nm) have been synthesized using trioctylphosphine (TOP) as a source of phosphorus. The method reported here is unconventional, quite rapid (~90min), more viable, less expensive and relatively greener as compared to other conventional methods that employ tristrimethylsilyylphosphine(P(SiMe3)3) which is scarce, expensive, flammable, highly toxic and even banned in a few countries. Highly luminescent InP QDs having bluish-green emission (λ~ 490nm) can be synthesized using this method without resorting to any post-synthesis etching to tune the emission to the blue region. Besides being the source of phosphorus and the particle size regulating agent, the efficacy of TOP is further realized during synthesis via its reduction of indium salt, which aids in the formation of indium metal and then subsequently in the development of InP QDs. The PL intensity of as-synthesized InP QDs is further enhanced by growing a shell of wide band gap material, i.e. ZnS resulting in a concurrent increment in quantum yield from ~25% to ~38% respectively.

Trace Amounts of Second Metal Elements Can Play a Key Role in the Generation of Organometallic Compounds

Abstract During the development of new synthetic organic reactions by the use of group 4–7 metals, we twice encountered a reproducibility problem. The key factor was trace amounts of second metal elements that contaminated the first, main metals, i.e., nickel in chromium and lead in zinc. We had determined the standard procedures for these reactions and they were adopted in Organic Syntheses. The difference in the source of zinc, i.e., contamination by a catalytic amount of lead, proved to affect both the reactivity of the Simmons–Smith reaction and the formation of alkylzinc from the corresponding iodides. By using the concept of catalytic effects of the second metals, we developed a method to use manganese metal and applied this to sequential radical and anionic reactions. In addition, allylic aluminum species were prepared smoothly from allylic halides and aluminum by addition of an indium salt, the second element. In this account, I describe how the synthetic methods were discovered and developed, with an emphasis on the stories behind the communications and articles.

Preparation and Gas Sensing Properties of In2O3/Au Nanorods for Detection of Volatile Organic Compounds in Exhaled Breath.

A series of In2O3/Au nanorods (NRs) were fabricated and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X–ray diffractometer (XRD) and X–ray photoelectron spectroscopy (XPS). The length to diameter ratios of In2O3/Au NRs was periodically modulated in the range of 2.9–4.5 through controlling the initial content of indium salt and reaction time. Their gas sensing properties to volatile organic compounds (VOCs) were carefully studied and then applied in exhaled breath detection. The results demonstrate that In2O3/Au NRs gas sensor can effectively detect acetone at 250 °C and ethanol at 400 °C. The corresponding actual detection limit is as low as 0.1 ppm to acetone and 0.05 ppm to ethanol, respectively. Moreover, by using humidity compensation method, In2O3/Au NRs gas sensor can clearly distinguish the acetone and ethanol biomarkers in human breath. The main reason of the enhanced gas sensing properties was attributed to the “spillover effects” between Au and In2O3 NRs. The excellent sensing performance indicates that In2O3/Au NRs is a promising functional material to actual application in monitoring and detecting diabetes and safe driving area in a noninvasive and more accurate way.

Efficient One‐Pot Synthesis of a Densely Functionalized Tetrahydropyridine in the Presence of [1,1′‐Binaphthalene]‐2,2′‐diol/Indium(III) Chloride (binol/InCl3) or Simple Brønsted Acids as Catalysts

AbstractThe highly functionalized tetrahydropyridine 4 was obtained in an indium(III) chloride catalyzed multi‐component reaction from benzaldehyde, 4‐methoxyaniline, and ethyl acetoacetate (=ethyl 3‐oxobutanoate) in the presence of [1,1′‐binaphthalene]‐2,2′‐diol (binol). It was found that binol played a beneficial role in this reaction, allowing a substantial decrease of the amount of indium salt. Also, simple organic Brønsted acids may serve as effective organocatalysts in this process.

ChemInform Abstract: Efficient Synthesis of α,β‐Diamino Acid Derivatives by In(III)‐Catalyzed Regioselective Addition of Amines to Aziridines.

Abstract An efficient catalytic method for the synthesis of α, β-diamino acid derivatives has been developed via regioselective ring opening of aziridines by amines in the presence of indium(III) salt under very mild reaction conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

In(OH)3particles from an ionic liquid precursor and their conversion to porous In2O3particles for enhanced gas sensing properties

The ionic liquid precursor tetrabutylammonium hydroxide (TBAH) is used to synthesize In(OH)3 particles. The ionic liquid TBAH is demonstrated to be effective for the synthesis of In(OH)3 nanorods with a controlled size. The effect of the indium salt and the added water amount on the final products is investigated. The synthesized In(OH)3 nanorods could be further transformed into porous In2O3 rod particles. Specifically, the gas sensing properties of the synthesized porous In2O3 rod particles to various organic compounds (methanol, ethanol, isopropanol, butanol, ethyl acetate and toluene) exhibit remarkable sensitivities, low detection limits and fast response–recovery times, which are superior to the reported In2O3 based sensors. The as-prepared porous In2O3 rod-based sensors thus demonstrate their potential applications in detecting chemical contaminants and dangerous gases.

Efficient Synthesis of α,β-Diamino Acid Derivatives by In(III)-Catalyzed Regioselective Addition of Amines to Aziridines

An efficient catalytic method for the synthesis of α, β-diamino acid derivatives has been developed via regioselective ring opening of aziridines by amines in the presence of indium(III) salt under very mild reaction conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

ChemInform Abstract: Development of Novel Synthetic Organic Reaction Based on Activation by a Trivalent Indium Salt

AbstractReview: ca. 50 refs.