Indium-tin Alloy Research Articles

Conductive Zeolite Supported Indium-Tin Alloy Nanoclusters for Selective and Scalable Formic Acid Electrosynthesis.

Upgrading excess CO2 toward the electrosynthesis of formic acid is of significant research and commercial interest. However, simultaneously achieving high selectivity and industrially relevant current densities of CO2-to-formate conversion remains a grand challenge for practical implementations. Here, an electrically conductive zeolite support is strategically designed by implanting Sn ions into the skeleton structure of a zeolite Y, which impregnates ultrasmall In0.2Sn0.8 alloy nanoclusters into the supercages of the tailored 12-ring framework. The prominent electronic and geometric interactions between In0.2Sn0.8 nanoalloy and zeolite support lead to the delocalization of electron density that enhances orbital hybridizations between In active site and *OCHO intermediate. Thus, the energy barrier for the rate-limiting *OCHO formation step is reduced, facilitating the electrocatalytic hydrogenation of CO2 to formic acid. Accordingly, the developed zeolite electrocatalyst achieves an industrial-level partial current density of 322mA cm-2 and remarkable Faradaic efficiency of 98.2% for formate production and stably maintains Faradaic efficiency above 93% at an industrially relevant current density for over 102 h. This work opens up new opportunities of conductive zeolite-based electrocatalysts for industrial-level formic acid electrosynthesis from CO2 electrolysis and toward practically accessible electrocatalysis and energy conversion.

Features of nanocontact formed using point electrical breakdown of a niobium oxide nanolayer

The electrical characteristics of a point section of niobium oxide between a massive cathode made of a superconducting indium-tin alloy and a niobium film before the oxide breakdown and the nanocontact that appears after the breakdown of the oxide at room temperature have been studied. The dependencies of the point breakdown voltage of the oxide and the resistance of nanocontacts on the method of breakdown and the thickness of the oxide in the range of 15–60 nm have been established. In particular, a minimum value of the breakdown current has been established (about 1 μA), below which breakdown does not occur. The voltage-current characteristic (VCC) of the oxide has a semiconductor character and indicates the dependence of the breakdown voltage of the oxide on its polarity. The VCC of the nanocontact is nonlinear, which is associated with phase transitions in the nanocontact material caused by its heating by the transport current.

Ternary Liquid Metal Polymer Composite for Stretchable Electronics

AbstractThe small strain characteristics of the traditional flexible conductive composites hinder their realization of skin‐like properties and multi‐scenario applications. The value of liquid metal (LM)‐based elastomers is demonstrated in flexible electronics. Attempts in this area include the development of multifunctional LM‐based elastomers with controllable morphology, superior mechanical performances, and excellent stability. In this work, an efficient strategy is proposed to achieve the fast preparation of the LM patch by uniformly distributing eutectic gallium–indium–tin alloy in deionized water and by constructing the LM‐iron particles‐Ecoflex (LMIE) ternary composite system. In this study, the fabricated LMIE large strain sensor exhibits high sensitivity (the gage factor (GF) = 0.98 when strain ranges from 0% to 60%; GF = 1.91 when strain ranges from 60% to 100%), high linearity (correlation coefficient (R2) = 0.96 when strain ranges from 0% to 60%; R2 = 0.99 when strain ranges from 60% to 100%), a wide strain range of detection (e.g., 1%–100%) and breaking elongation (e.g., 450%), a fast response time (80 ms), excellent repeatability and stability. This work exhibits the excellent potential of multifunctional liquid metal composites in wearable electronics and prediction devices of structural collapse.

Liquid Metal Embedded Elastomers as High-performance S-TIM Replacements

Thermal interface materials are used as part of comprehensive thermal management strategies in modern electronic devices, ranging from personal computers to automotive and server applications. One crucial material is the thermal interface material that goes in between the die and heat spreader, called the TIM1 material. Key desirable properties of TIM1 materials include: easy application, low thermal resistance, high electrical resistivity, and robustness to thermal cycling and bake. Aiming to achieve these properties, popular choices of TIM1 include gap fillers (rubbery thermal pads), thermal greases (fluidlike polymer TIMs with suspended metal-oxide particles such as aluminum and zinc oxides), solid TIMs (such as sintered silver and indium), and liquid metals (such as Gallium Indium Tin alloys). However, as power densities in semiconductor packages have increased dramatically in recent years, thermal engineers are finding it difficult to find TIMs that have suitably low thermal resistance and can survive the attendant extreme thermal cycling profiles. Recently, researchers have proposed using liquid metal embedded elastomers (LMEEs) as thermal interface materials, leading to Arieca Inc. developing a TIM1 LMEE suitable for the most demanding of applications. In this presentation, we explore the application of LMEEs as a TIM1, subjecting LMEEs to a test suite spanning a wide range of material properties, ranging from complex viscosity to DSC, TGA, and even measuring thermal resistance before and after applying strains of 380% to an interface bonded together using only LMEE. We find that by adjusting the polymer composition, cure temperatures can be tuned, without significantly affecting thermal reliability. Additionally, we observe thermal resistance approaching 2 mm2K/W in an ASTM D5470 test setup, and highlight how this range of properties can be used to directly bond two surfaces together without a lid sealant and maintain good thermal contact. Finally, we conclude with some remarks to highlight the expanding opportunities on the technological frontier opened up by this class of advanced packaging materials.

An Oscillation System Based on a Liquid Metal Droplet and Pillars under a Direct Current Electric Field.

Gallium-based liquid metal is a new class of material that has attracted extensive attention due to its excellent deformation characteristics and great potential in applications. Based on the deformation characteristics of liquid metal droplets, researchers have developed many oscillation systems composed of gallium indium tin alloy (GaInSn) droplet and graphite, or aluminum-doped gallium indium alloy (Al-GaIn24.5) droplet and iron, and so on. Rather than the oxidation and deoxidation mechanisms used in previous systems, an oscillation system that can achieve gallium indium alloy (EGaIn) droplet oscillation with the frequency of 0-29 Hz is designed depending on the interactions between the electric field, pillars, sodium hydroxide, and the droplet. The forces on the droplet are analyzed specifically, which have a great influence on droplet deformation. Additionally, the effects of factors such as voltage, the concentration of sodium hydroxide (NaOH) solution, and droplet size on the droplet oscillation are elucidated based on the force analysis, enabling the flexible control of the oscillation frequency and amplitude of the droplet. This work provides a new perspective on the design of oscillation systems and further enhances our understanding of the deformation of gallium-based liquid metal droplets.

Reduction mechanism of spent ITO target in CaCl2 molten salt

In-Sn alloys were recycled by direct reduction of spent ITO (s-ITO) target in molten calcium chloride at 850 °C. The electro-deoxidation mechanism of s-ITO was investigated by electrolysis at different voltages and different electrolysis times. In the electro-deoxidation process, s-ITO was first formed with CaO to form CaIn2O4, CaSnO3 and Ca2SnO4, and then it was reduced into In-Sn alloy. Under constant voltage electrolysis at 2.2 V for 3 h, 2 g of s-ITO can be completely reduced to indium-tin alloy. Various contents of CaO were added to molten salt to study the effect of CaO on the reduction process. After immersing the s-ITO block in CaCl2 and CaO-CaCl2 for different times, it was found that the addition of CaO inhibited the dissolution of s-ITO. Potentiostatic electrolysis was performed in CaCl2 containing 0–3 mol% CaO for 3 h, and it was investigated that with the increase of CaO content, the alloy yield increased, while the current efficiency gradually decreased.

Visible photocatalytic properties of Ag–Ag2O/ITO NWs fabricated by mechanical injection-discharge-oxidation method

In the present study, anodic aluminum oxide (AAO) plates with a pore size of 40 nm were used as templates to fabricate indium-tin (In9Sn1) alloy nanowires (NWs) by vacuum mechanical injection method, and then Ag nanoparticles were coated onto the surface of the In9Sn1 NWs by means of the “in-situ discharge reduction” method. Finally, the composites were exposed in air for heat treatment to synthesize Ag–Ag2O/indium-tin oxide (ITO) NWs. The morphology, composition, and structure of the obtained samples were identified using scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction analysis. The results show that the length of the In9Sn1 NWs is 69.6 μm and Ag nanoparticles with 5–10 nm are uniformly coated on the surface of the In9Sn1 NWs, after calcination in air, Ag/In9Sn1 NWs are oxidized to Ag–Ag2O/ITO NWs. Additionally, the photocatalytic property of Ag–Ag2O/ITO NWs is tested, and it reveals the good photocatalytic activity thereof for the degradation of methylene blue under visible light irradiation.

Preparation of In/Sn Nanoparticles (In3Sn and InSn4) by Wet Chemical One-Step Reduction and Performance Study

The preparation of binary alloys by surfactant-assisted chemical reduction in aqueous solution at room temperature has become a hot topic. In this article low melting point tin/indium (Sn/In) nanoparticles are synthesized. The formation process of the alloy was studied. Scanning electron microscopy, energy spectrometry, and X-ray diffraction are used to determine the morphology, composition, and crystal structure of the nanoparticles. Study found that fully alloyed indium-tin nanoparticles can be obtained by wet chemical method and the main phases of indium-tin alloy are β-phase (In3Sn) and γ-phase (InSn4). However, the Sn phase appears at a low content of indium (40 wt%). When the content of indium increases to 45 (wt%), the tin phase disappears. In addition, the most important finding is that the composition of the indium-tin alloy can be changed by ratio control, and the content of In3Sn increases with the increase of indium content. The relative content of In3Sn attains a maximum when the content of indium increases to 60 (wt%). In contrast, the content of InSn4 decreases. Finally, differential scanning calorimetry measurements is performed to understand the melting behavior of the nanoparticles and low melting temperatures are achieved for a wide range of indium compositions (from 40% to 60%). The melting temperature is found to be in the range of 125–132 °C and it increased with increasing In3Sn (also the increase of indium content). This gives us a new understanding into the binary alloy nano-system and gives important information for the application of low temperature alloy solders. The choice of composition can be based on the corresponding melting point.

Recovery and Reuse of Spent ITO Targets through Electrochemical Techniques

Indium is a strategically scarce metal with excellent conductivity and light transmittance that is widely used to prepare ITO targets. In this work, an electrolysis method was exploited to recover and reuse spent ITO (s-ITO) targets to provide a novel way to recycle valuable resources. The electrochemical behaviors of indium tin oxide were studied first by cyclic voltammetry in CaCl2 at 850 °C. A reduction peak corresponding to the simultaneous reduction of indium tin oxide was found at −0.5 V vs Pt. Then, indium-tin alloy was recovered by electrolysis of s-ITO particles in CaCl2 at −2.8 V and 850 °C. The mass ratio of In and Sn in the alloy obtained by electrolysis is almost the same as that in the initial s-ITO before electrolysis. In addition, oxide composite powders were obtained by electrolysis of the alloy in NH4Cl aqueous solution, which can be used to synthesize ITO targets. The particle size of the composite powders was between 20 nm and 60 nm, and the distribution of each element was uniform.

Unveiling the Magnesium Storage Mechanisms of Co-Sputtered Indium-Tin Alloy Films Using Operando X-ray Diffraction

Tin (Sn)-based anodes have drawn extensive attention for magnesium ion batteries (MIBs) owing to their low reaction potentials, high theoretical capacities, and compatibility with conventional electrolytes. However, their poor electrochemical reactivity, sluggish kinetics, and large volume changes have obstructed progresses. Additionally, a clear understanding of the Mg storage chemistry is crucial for the development of high-performance MIBs. Here, we prepared self-supporting In-Sn alloy films with different compositions and phase constitutions via a one-step magnetron co-sputtering. As benchmarked with pure Sn film, the single-phase and biphase In-Sn alloy films effectively trigger the alloying reaction of Sn with Mg and further increasing of In significantly improves the electrochemical reactivity of the In-Sn electrodes. More importantly, operando X-ray diffraction was performed to unveil the magnesiation/demagnesiation mechanisms of the In0.2Sn0.8, In0.2Sn0.8/In3Sn and In3Sn electrodes, showing that In0.2Sn0.8 and In3Sn display different Mg storage mechanisms when existing alone or biphase coexisting. Our findings highlight the significance of the electrode design and mechanism investigations for MIBs.

Synthesis and research of polyfunctional silylureas used in electric deposition of tin-indium alloy

Polyfunctional silylureas were synthesized by the interaction of 3-aminopropyltriethoxysilane with isocyanates of various structures in an inert aromatic solvent. Commercially available diisocyanates such as isophorone diisocyanate, hexamethylene diisocyanate, 2,4-toluene diisocyanate were used as isocyanates. In this case, freshly distilled toluene was used as a solvent. The structures of the obtained compounds were confirmed by the data of IR and NMR1H spectroscopy. Using the synthesized compounds, formulations of compositions for electrodeposition of a tin-indium alloy on a copper wire were developed. The possibility of using silylureas of various structures as effective surfactants used in the electrodeposition of the tin-indium alloy is shown. The operational characteristics of the obtained wire were investigated, including the wire diameter, coating thickness, tensile strength, electrical resistance, and direct current electrical resistivity.

Electrical, optical and photoconductive properties of Sn-doped indium sulfofluoride thin films

This work reports on undoped and Sn-doped indium sulfofluoride thin-films deposited by radio-frequency plasma-enhanced reactive thermal evaporation. The deposition was performed evaporating pure indium or indium-tin alloy in SF6 plasma at substrate temperatures ranging from 373 to 423 K. Rutherford backscattering analysis and secondary-ion mass spectrometry were used to determine the chemical composition of the films. The film characterization includes electrical, optical, and photoconductivity measurements. The resistivity of undoped material varies in a wide range of 1 GΩ-cm to 2 TΩ-cm depending on deposition conditions. Sn doping leads to a decrease in the resistance down to 8 MΩ-cm. The films are highly transparent in the visible-infrared region due to an indirect bandgap of 2.7–3 eV. Moreover, the doped material is highly photosensitive in the blue - UV region. Photoconductivity kinetics under various excitation conditions was also studied. The synthesized material is a promising candidate for a buffer layer in chalcogenide-based solar cells.

Thermal-Hydraulic Analysis on Quench Behavior of Indium-Tin Soldered REBCO Composite Conductor

The second-generation high-temperature superconductor REBCO is one of the most valuable candidates that meet the requirements of future magnetic confinement fusion device. Quench behavior of an improved high-current REBCO composite conductor is simulated by a 1-D finite element method. Indium-tin alloy foil placed in the gap between stabilizer, jacket, and superconducting tape stacks can significantly reduce thermal contact resistance, which leads to an increase on the minimum quench energy of composite conductor. Short perturbations have a better response to this improvement than long perturbations, due to the low normal zone propagation velocity (NZPV) of REBCO conductor. For short perturbation (perturbation length (l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> = 0.1 m), the peak temperature in cable and helium drops 12.76 and 17.99%, respectively, after soldered. Due to the change of heat transfer in a composite conductor caused by helium wave propagation, the development and maximum length of normal zone significantly decrease from 13.06 to 4.78 m under long perturbation (l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</sub> = 10 m) circumstance. High current REBCO composite conductor with proper indium-tin alloy soldered can enhance the stability and safety of composite conductors under severe working conditions, but it also slows down the NZPV and hinders the quench detection of high-temperature superconducting magnet.

Thermoplastic Elastomer Phase Changing Materials for Stiffness Modulation

Four natural rubber-based phase changing materials (PCMs) were synthesized and evaluated with the goal of achieving controlled stiffness modulation at elevated temperatures (∼100-120 °C). The phase changing was achieved through either the glass transition or melt transition of one of four phase changing fillers: polystyrene, poly(methyl methacrylate), low density polyethylene, and indium tin alloy. The PCM stiffness was analyzed using dynamic mechanical analysis and the results showed that all four PCMs exhibited two thermal transitions: a low temperature transition at −58 °C due to the glass transition of the natural rubber matrix and a high temperature transition at ∼100-120 °C due to the thermal transitions in the four filler materials. The degree of stiffness change of all PCMs at 100-120 °C was found to be strongly influenced by the type of the phase changing filler as well as the type of thermal transition (glass transition versus melt transition). The compatibilities of the phase changing materials were analyzed using the Flory-Huggins interaction parameter and it was shown that natural rubber and low density polyethylene had the best compatibility. All systems exhibited effective stiffness modulation with the change in temperature, enabling them to be used for applications requiring variable stiffness control.

Униполярный электродвигатель сервопривода с магнитной системой на основе высокотемпературных сверхпроводников

In this work the design of a homopolar motor prototype is proposed. The magnetic system consists of a high temperature superconducting (HTS) stator and a disc rotor with liquid metal sliding electric contacts made of gallium indium tin alloy. The estimation of magnetic fields and torques is performed for the device. The possibility of using this motor as a servo actuator is considered. The results of the preliminary experimental attempts to control a single
pole motor based on permanent magnets by means of a proportional–integral–derivative (PID) algorithm are presented.

Structure of tin-indium alloys in condensed films

The work is devoted to the study of the microstructure of In-Sn films condensed onto the glass substrate. The samples for the study were obtained by the method of variable composition and variable state with the use of sequential condensation of components. The use of this technique allowed us in a direct manner to observe the main outlines of the phase diagram of the studied binary system on the substrate. The visualization of phase equilibrium lines is provided by the differences in the light scattering by different parts of the sample. These differences were attributed to the peculiarities of the morphological structure of films, which correspond to different phase state of the binary system. It was established that, above the liquidus line in the studied films, due to the self-assembly processes, arrays of separate spherical particles with a unimodal size distribution are formed.

Electrodeposition of Sn–In Alloys Involving Deep Eutectic Solvents

Tin–indium alloys represent attractive lead-free solder candidates. They show lower values of melting point than pure indium, so that they are investigated as materials with significant applications potential in the electronic industry. Electrodeposition is a very convenient route to prepare Sn–In alloys. The paper presents several experimental results regarding the electrodeposition of Sn–In alloy coatings involving deep eutectic solvents (DESs), namely using choline chloride-ethylene glycol eutectic mixtures. The influence of the main operating parameters on the Sn–In alloy composition and characteristics are presented. Adherent and uniform Sn–In alloy deposits containing 10–65 wt % In have been obtained on Cu substrates. The In content was found to increase as both the In:Sn molar concentration ratio of ionic species in the electrolyte and the applied temperature increased. The use of pulsed current allowed the use of higher current densities leading to slightly higher values of In content in the alloy deposit. X-ray diffraction (XRD) analysis revealed the presence of InSn4 and In3Sn phases in agreement with the phase diagram. According to thermogravimetric analysis (TGA) measurements, values of melting points in the range of 118.6 and 127.5 °C were obtained depending on the alloy composition. The solder joints’ behavior and alloy coatings corrosion performance were also discussed.

Synthesis of InSn alloy superconductor below room temperature

The eutectic point for a typical gallium indium tin (GaInSn) alloy with an atomic composition of 78% Ga, 15% In, and 7% Sn is at near room temperature. This alloy exists in the liquid state at room temperature and solidifies below 260 K. We found that the major In3Sn and minor InSn4 superconducting phases are formed in this liquid alloy below 260 K and this alloy exhibits superconductivity at 6.0 K. Therefore, we can fabricate superconducting thick films without heat treatment by simply coating a substrate with the alloy and subsequently cooling it to the alloy's superconducting transition temperature.

Fabrication of Atom Probe Tomography Specimens from Nanoparticles Using a Fusible Bi-In-Sn Alloy as an Embedding Medium.

We propose a new method for preparing atom probe tomography specimens from nanoparticles using a fusible bismuth-indium-tin alloy as an embedding medium. Iron nanoparticles synthesized by the sodium borohydride reduction method were chosen as a model system. The as-synthesized iron nanoparticles were embedded within the fusible alloy using focused ion beam milling and ion-milled to needle-shaped atom probe specimens under cryogenic conditions. An atom probe analysis revealed boron atoms in a detected iron nanoparticle, indicating that boron from the sodium borohydride reductant was incorporated into the nanoparticle during its synthesis.

Electron-beam irradiation induced phase transformation, optical absorption and surface-enhanced Raman scattering of Indium tin alloy thin films

Electron beam (EB) irradiation experiments on Indium-tin (In-Sn) alloy thin films are reported. The structure and the optical properties of the samples were investigated by atomic force microscopy, X-ray diffraction, UV-vis-NIR double beam spectrometer and Raman system, respectively. Those results show that EB irradiation has the effects of changing the preferred orientation, improving the crystalline, enhancing the absorption, and improving the surface-enhanced Raman scattering (SERS) of samples. In addition, Finite-Difference Time-Domain (FDTD) was performed for the surface plasmon resonance properties of the as-irradiated samples, and the results are in good agreement with the experiments.