Sn Components Research Articles

Morphology Variation of Ternary PdCuSn Nanocrystalline Assemblies and Their Electrocatalytic Oxidation of Alcohols.

Metal alloys not only increase the composition and spatial distribution of elements but also provide the opportunity to adjust their physicochemical properties. Recently, multimetallic alloy nanocatalysts have attracted great attention in energy applications and the chemical industry. This work presents the production of three ternary PdCuSn nanocrystalline assemblies with similar compositions via a one-step hydrothermal method. The shape variation of assembly units from nanosheets and nanowires to nanoparticles were realized by adjusting the percentage of Sn in metal precursors. Experimental data show that PdCuSn nanowire networks showed the best catalytic activity by virtue of their optimized morphological characteristics and microscopic electronic structure. With electrooxidation of methanol, ethanol, ethylene glycol, and glycerol at 30 °C, PdCuSn nanowire networks demonstrated catalytic activity of 1129, 2111, 2540, and 1445 mA mg-1, respectively. The catalytic activity for alcohol oxidation is attributed to the production of the electronic structure and morphology features that are most suitable. This is achieved by introducing the proper quantities of Cu and Sn components in the first stage of synthesis. This study would help with the construction of high-efficiency nanostructured alloy catalysts by regulating the electronic structure and morphology.

Synchronized crystallization in tin-lead perovskite solar cells

Tin-lead halide perovskites with a bandgap near 1.2 electron-volt hold great promise for thin-film photovoltaics. However, the film quality of solution-processed Sn-Pb perovskites is compromised by the asynchronous crystallization behavior between Sn and Pb components, where the crystallization of Sn-based perovskites tends to occur faster than that of Pb. Here we show that the rapid crystallization of Sn is rooted in its stereochemically active lone pair, which impedes coordination between the metal ion and Lewis base ligands in the perovskite precursor. From this perspective, we introduce a noncovalent binding agent targeting the open metal site of coordinatively unsaturated Sn(II) solvates, thereby synchronizing crystallization kinetics and homogenizing Sn-Pb alloying. The resultant single-junction Sn-Pb perovskite solar cells achieve a certified power conversion efficiency of 24.13 per cent. The encapsulated device retains 90 per cent of the initial efficiency after 795 h of maximum power point operation under simulated one-sun illumination.

High-speed GeSn resonance cavity enhanced photodetectors for a 50 Gbps Si-based 2 μm band communication system

Expanding the optical communication band is one of the most effective methods of overcoming the nonlinear Shannon capacity limit of single fiber. In this study, GeSn resonance cavity enhanced (RCE) photodetectors (PDs) with an active layer Sn component of 9%–10.8% were designed and fabricated on an SOI substrate. The GeSn RCE PDs present a responsivity of 0.49 A/W at 2 μm and a 3-dB bandwidth of approximately 40 GHz at 2 μm. Consequently, Si-based 2 μm band optical communication with a transmission rate of 50 Gbps was demonstrated by using a GeSn RCE detector. This work demonstrates the considerable potential of the Si-based 2 μm band photonics in future high-speed and high-capacity optical communication.

Sn component gradient GeSn photodetector with 3 dB bandwidth over 50 GHz for extending L band telecommunication.

In this work, high-performance GeSn photodetectors with a Sn content gradient GeSn layer were fabricated on SOI substrate by CMOS-compatible process for C and L band telecommunication. The active GeSn layer has a Sn component increased from 9 to 10.7% with the controlled relaxation degree up to 84%. The responsivities of GeSn detectors at 1550 nm and 1630 nm are 0.47 A/W and 0.32 A/W under -4 V bias, respectively. Over 50 GHz 3 dB bandwidth with the eye pattern about 70 Gb/s was also evidenced at 1630 nm. These results indicate that the GeSn photodetectors have a promising application for extending the silicon photonics from C band to L band.

Tuning phase stability and interfacial dipole for efficient methylammonium-free Sn-Pb perovskite solar cells

The oxidizability and fast crystallization of Sn(II) components commonly cause Sn/Pb phase separation and uncoordinated ion defects on Sn-Pb perovskite film surface. Here, 4-hydroxyphenethylamine hydrochloride (OHPEACl) is introduced to post-treat the Cs0.25FA0.75Pb0.5Sn0.5I3 perovskite film. The ammonium (-NH3+) and reductive phenol hydroxyl (-OH) in OHPEACl are verified to form ionic and hydrogen bonds with organic (FAI) or inorganic components (CsI, SnI2, and PbI2), thereby inhibiting Sn2+ oxidation, anchoring multiple defects sites (unbonded Pb2+, Sn2+, and I-), and promoting uniform distribution of Sn-Pb phases on the film surface. Furthermore, the 4-hydroxyphenethyl ammonium (OHPEA+) with high dipole moment of 9.93 Debye is proved to form reduced and uniform potential landscape of interface dipole, hence aligning energy levels and suppressing non-radiative recombination. Consequently, this strategy raised the efficiency of device from 17.94% to 20.20%, and realized a Voc of 0.84 V for methylammonium (MA) free Sn-Pb device. The unencapsulated devices displayed improved thermal stability at 85 ℃ for 500 h and enhanced continuous operation stability at MPP for 150 h. This approach of introducing multifunctional groups while constructing the interfacial dipole provides a new perspective for improving the quality of Sn-Pb perovskite films.

Structural, optical, XPS, and magnetic properties of Sn–O nanoparticles

Sn–O nanoparticles ranging in average particle sizes from 13 to 420 nm have been prepared by levitation-jet aerosol synthesis through condensation of tin vapor in a mixed flow of inert gases and air/oxygen. XRD established the presence of mixed-phase of Sn, SnO, and SnO2 components in the nanoparticles. During optical measurements, the redshift of bandgaps was discovered in nanoparticles with SnO2 content <80% and blue shift in nanoparticles with SnO2 content >80%. The results indicate that the nanoparticles exhibit room-temperature ferromagnetism. The maximum net saturation magnetization observed in the studied nanoparticles is ≈ 7 memu/g near a Sn/O molar ratio of ≈0.58. Moreover, an excess magnetic contribution, either as paramagnetic or as diamagnetic susceptibility, has been observed. Raman studies found the presence of small amounts of Sn3O4 or Sn2O3 phases in the nanoparticles. The presence of oxygen vacancies in the nanoparticles was established by XPS. Their density increase accompanies by the saturation magnetization enhancement. We propose that the presence of definite localized states, like interacting and non-interacting vacancies on the Sn/SnO and SnO/SnO2 interfaces, is responsible for the observed magnetic phenomena.

Enhanced activation of H2O2 by bimetallic Cu2SnS3: A new insight for Cu (II)/Cu (I) redox cycle promotion

HypothesisDespite that the development of Cu2SnS3 (CTS) catalyst has attracted increasing interests, few study has reported to investigate its heterogeneous catalytic degradation of organic pollutants in a Fenton-like process. Furthermore, the influence of Sn components towards Cu (II)/Cu (I) redox cycling in CTS catalytic systems remains a fascinating research. ExperimentsIn this work, a series of CTS catalysts with controlled crystalline phases were prepared via a microwave-assisted pathway and applied in the H2O2 activation for phenol degradation. The efficiency of phenol degradation in CTS-1/H2O2 system (CTS-1: the molar ratio of Sn (copper acetate) and Cu (tin dichloride) is determined to be Sn:Cu = 1:1) was systematically investigated by controlling various reaction parameters including H2O2 dosage, initial pH and reaction temperature. We discovered that Cu2SnS3 exhibited superior catalytic activity to the contrast monometallic Cu or Sn sulfides and Cu (I) acted as the dominant active sites. The higher Cu (I) proportions conduce to the higher catalytic activities of CTS catalysts. Quenching experiments and electron paramagnetic resonance (EPR) further proved that the activation of H2O2 by CTS catalyst produces reactive oxygen species (ROS) and subsequently leads to degradation of the contaminants. A reasonable mechanism of enhanced H2O2 activation in Fenton-like reaction of CTS/H2O2 system was proposed for phenol degradation by investigating the roles of copper, tin and sulfur species. FindingsThe developed CTS acted as a promising catalyst in Fenton-like oxidation progress for phenol degradation. Importantly, the copper and tin species contribute to a synergetic effect for the promotion of Cu (II)/Cu (I) redox cycle, which thus enhanced the activation of H2O2. Our work may offer new insight on the facilitation of Cu (II)/Cu (I) redox cycle in Cu-based Fenton-like catalytic systems.

The Optical Light Curve of GRB 221009A: The Afterglow and the Emerging Supernova

We present extensive optical photometry of the afterglow of GRB 221009A. Our data cover 0.9–59.9 days from the time of Swift and Fermi gamma-ray burst (GRB) detections. Photometry in rizy-band filters was collected primarily with Pan-STARRS and supplemented by multiple 1–4 m imaging facilities. We analyzed the Swift X-ray data of the afterglow and found a single decline rate power law f(t) ∝ t −1.556±0.002 best describes the light curve. In addition to the high foreground Milky Way dust extinction along this line of sight, the data favor additional extinction to consistently model the optical to X-ray flux with optically thin synchrotron emission. We fit the X-ray-derived power law to the optical light curve and find good agreement with the measured data up to 5−6 days. Thereafter we find a flux excess in the riy bands that peaks in the observer frame at ∼20 days. This excess shares similar light-curve profiles to the Type Ic broad-lined supernovae SN 2016jca and SN 2017iuk once corrected for the GRB redshift of z = 0.151 and arbitrarily scaled. This may be representative of an SN emerging from the declining afterglow. We measure rest-frame absolute peak AB magnitudes of M g = −19.8 ± 0.6 and M r = − 19.4 ± 0.3 and M z = −20.1 ± 0.3. If this is an SN component, then Bayesian modeling of the excess flux would imply explosion parameters of M ⊙, M ⊙, and km s−1, for the ejecta mass, nickel mass, and ejecta velocity respectively, inferring an explosion energy of E kin ≃ 2.6–9.0 × 1052 erg.

Formation mechanism and characteristics of Au-Sn-O and Sn-O nanocompounds with various band gaps through flame chemical vapor deposition process

After forming the double layer of SnO2 and Au, the compound of Sn and O with multiple band gaps was formed in a short time period via flame chemical vapor deposition (FCVD). The Sn component of SnO2 has fluidity and is the only one moving to the discrete Au side and leaving O behind. The capillarity of Sn allows it to form a unique structure with Au-Sn-O nanoparticles and amorphous Sn-O nanotubes of multiple compositions in a single process. For verification, the gradual morphological, crystallographic, compositional, and optical changes in the material were sequentially presented as per the degree of FCVD.

Effect of Laser Pulse Width and Intensity Distribution on the Crystallographic Characteristics of GeSn Film

Germanium-tin (GeSn) alloy is considered a promising candidate for a Si-based short-wavelength infrared range (SWIR) detector and laser source due to its excellent carrier mobility and bandgap tunability. Pulsed laser annealing (PLA) is one of the preeminent methods for preparing GeSn crystal films with high Sn content. However, current reports have not systematically investigated the effect of different pulse-width lasers on the crystalline quality of GeSn films. In addition, the intensity of the spot follows the gaussian distribution. As a result, various regions would have different crystalline properties. Therefore, in this study, we first provide the Raman spectra of several feature regions in the ablation state for single spot processing with various pulse-width lasers (continuous-wave, nanosecond, femtosecond). Furthermore, the impact of laser pulse width on the crystallization characteristics of GeSn film is explored for different single-spot processing states, particularly the Sn content incorporated into GeSn crystals. The transient heating time of the film surface and the faster non-equilibrium transition of the surface temperature inhibit the segregation of the Sn component. By comparing the Raman spectra of the pulsed laser, the continuous-wave laser shows the most acute Sn segregation phenomenon, with the lowest Sn content of approximately 2%. However, the femtosecond laser both ensures crystallization of the film and effective suppression of Sn expulsion from the lattices, and the content of Sn is 8.07%, which is similar to the origin of GeSn film.

High-throughput XPS spectrum modeling with autonomous background subtraction for 3 d 5/2 peak mapping of SnS

We propose a fitting model that automatically conducts the background subtraction during high-throughput peak fitting. The fitting model consists of the pseudo-Voigt mixture model and the ramp-sum background model, and each model represents the peak and background component, respectively. The optimization of the fitting model is performed by the spectrum adapted ECM algorithm that enables us to perform the peak fitting and background subtraction simultaneously through the high-throughput calculation. Application of the proposed model to the synthetic spectral data showed appropriate decomposition of the peak and background component. We also applied the proposed model to 3721 spectral data collected from the SnS sheet by X-ray photoelectron spectroscopy. The spectral data from the SnS sheet were successfully decomposed to the component of Sn 3d3/2 peak, Sn 3d5/2 peak and background, respectively. As the spectrum adapted ECM algorithm can efficiently analyze a large amount of spectral data, we can obtain the color map showing spatial distribution of Sn(II) and Sn(IV) using the parameter of Sn 3d5/2 peak. The proposed model supports us to obtain the insightful spatial distribution of peak component that has been difficult to obtain by conventional peak fitting.

Pattern Formation by Spinodal Decomposition in Ternary Lead-Free Sn-Ag-Cu Solder Alloy

In comparison to Pb-based solders which have a toxic effect, the tin-silver-copper (SAC) family of alloys have relatively strong reliability and are widely used in the electronics industry. Phase separation and coarsening phenomenon on the surface of 96.5 wt. % Sn-3.0 wt. % Ag-0.5 wt. % Cu (SAC305) solder products exhibit special microstructural features and offer opportunities for the microstructure control of microelectronic interconnects. However, the formation mechanism of such morphological patterns is still unknown. Here, we applied a combination of experimental and phase field methods to study how such patterns form. It was observed that the pattern was Sn-rich and exhibited the characteristic morphology of spinodal decomposition. Contrary to earlier findings that only binary systems like Sn-Pb and Sn-Bi experienced such phenomena, spinodal decomposition was firstly observed in ternary solder system Sn-Ag-Cu. Morphology of Sn-rich patterns depended on whether the spinodal decomposition reacted completely. SAC305 solder alloy was easily decomposed by Sn component after being heated to roughly 260 °C. The above conclusions could offer theoretical support for quantitatively controlling the microstructure of solder alloys and would enhance the quality of related products.

Significant refinement and spheroidization of harmful Fe-rich phases in Al–Cu–Mg alloys by small Sn addition

Solidification phases of conventional cast aerospace Al–Cu–Mg alloys and their evolution during homogenization were comprehensively studied. Significant refinement and spheroidization of solidification phases were found by the addition of 0.04, 0.15, and 1.00 mass % Sn to Al–Cu–Mg alloys. The soluble Sn component is dissolved in the Al matrix as solute atoms, while Sn in excess of the solid solubility segregates in the intradendrites in the form of Sn pools with a size (diameter) of one-half to several micrometers. These solute Sn atoms and Sn pools can capture Cu, Mg, and Fe atoms or hinder their diffusion into the residual liquid phase in the interdendritic region during solidification. Owing to the Sn addition, the contents of the Al2Cu, Al2CuMg, and Al7Cu2Fe phases in the interdendritic region are greatly reduced, thereby leading to significant refinement and spheroidization of these solidification phases. The formation of proeutectoid Mg2Sn phases is also found to be effective for the refinement of solidification phases.

Structural, optical, magnetic, and XPS properties of SnOx nanoparticles

SnOx nanoparticles ranging in average particle sizes from 13 to 420 nm have been prepared by levitation-jet aerosol synthesis through condensation of tin vapor in a mixed flow of inert gases and air/oxygen. X-ray diffraction (XRD) established the presence of mixed-phase of Sn, SnO, and SnO2 components in the nanoparticles. During optical measurements, the redshift of bandgaps was discovered in nanoparticles with SnO2 content <80% and blue shift in nanoparticles with SnO2 content >80%. The samples were examined for their magnetic properties using a vibrating sample magnetometer (VSM) and indicate room-temperature ferromagnetism. The maximum net saturation magnetization observed in the studied nanoparticles is ≈ 7 memu/g near a Sn/O molar ratio of ≈0.58. Moreover, an excess magnetic contribution (from oxygen vacancies), either as paramagnetic or as diamagnetic susceptibility, has been observed. Raman studies found the presence of small amounts of Sn3O4 or Sn2O3 phases in the nanoparticles. The presence of oxygen vacancies in the nanoparticles was established by X-ray photoelectron spectroscopy (XPS). Their density increase is probably accompanied by the saturation magnetization enhancement. We propose that the presence of definite localized states, like interacting and non-interacting vacancies on the Sn/SnO and SnO/SnO2 interfaces, is responsible for the observed magnetic phenomena.

The analysis of the level of emission characteristics depending on the aerosol structure

An attempt to combine the main verified recommendations for the organization of low-emission combustion of fuels (in relation to three main components of standardized harmful substances SN, NOx, and CO2) into one of the crucial modern problemsis implemented. Thepaper is devoted to the search for some general trends in the formation of emission characteristics based on the accumulated experience such as computational and experimental results obtained in CIAM.

A hybrid optimization-Machine Learning approach for the VNF placement and chaining problem

Virtual Network Function Placement and Chaining Problem focuses on allocation of customers demand’s on the Substrate Network. Among other factors, an optimal allocation of resources is hampered by nature of the online problem and by its complexity. Since we are dealing with an NP-hard combinatorial problem, while the number of network components grows linearly, the computational processing and runtime increase exponentially. Therefore, an application of Machine Learning techniques to reduce the number of components present in the SN is proposed in this work. In particular, we have developed clustering techniques that aim to find groups of promising components to map customer demands and disregard those that are less promising. Two different clustering models are proposed: (i) based on the Spatial Location of the SN components; and (ii) based on SN’s historical resource consumption data. An Integer Linear Programming model is proposed to evaluate the different simulation scenarios. Both approaches reduced the execution time (≈75%) and the end-to-end delay of virtual requests, in addition to keeping the acceptance rate and profit stable compared to the exact approach.

Parametric optimization of tribological properties on magnesium - tin – SiC composites

In the current examination, the consolidated impact of tin (Sn) component and Silicon Carbide (SiC) artistic particles on magnesium over its tribological attributes is researched. The composite examples were readied utilizing the powder metallurgy procedure and the level of tin is differed from 5 to 15% in steps of 5% by weight keeping SiC weight portion consistent. A symmetrical exhibit dependent on Taguchi's strategy will be viewed as dependent on the shifting levels and factors considered and the preliminaries will be led to advance the boundaries in like manner. The control factors considered in this examination incorporates weight division of SiC and tin, load, sliding speed and separation. The yield reaction included wear rate and frictional coefficient esteems which is to be researched utilizing a pin-on-circle sliding wear testing according to ASTM G99. The correlation of the tribological conduct of the created composite examples with unadulterated magnesium prepared through powder metallurgy is completed and SEM micrographs of the exhausted surface are gotten to examine the wear components. The other mechanical properties of the blend are assessed to consider the impact of the mix on Magnesium.

Investigating Liquid Metal Galinstan as a High Current Carrier and Its Interaction with Collector Electrodes

In this work, we demonstrate the potential application of liquid metal galinstan as a means of carrying high currents between two collector electrodes. The room-temperature liquid metal was placed between two electrodes made either of stainless steel (SS) or of copper, where the electrical performance at applied currents as high as 250 A was monitored and found to be highly stable. The surface interaction between galinstan and the collector electrodes in the presence and absence of such high DC currents was also investigated. After 12 h of contact with Cu electrodes, analysis by X-ray diffraction and energy-dispersive X-ray experiments revealed the presence of Ga and Cu as well as evidence of very minor InSn phase separation from liquid galinstan to form a solid alloy. However, after the application of a DC current of 250 A for 12 h, extensive Cu-Ga alloy formation was observed in the form of CuGa2, as well as a more pronounced phase separation of the In and Sn components into islands of InSn. It was found that the slight temperature rise during electrical testing favored alloy formation but was not the origin of the phase separation of the In-Sn components. In contrast, analysis of the SS electrode after 24 h of an applied DC current of 250 A did not reveal any form of alloy formation. This work shows that the electrical performance of liquid metal galinstan is stable upon the application of high DC currents using two different contact materials even though the interaction with the contacts differs. In addition, this provides an interesting pathway that can be explored for alloy production using galinstan and Cu materials under the application of an applied current, which may have other uses apart from high-current-density carriers.

Calculation of Ge1-xYx (Sn, Pb) work function along (100), (110), (111) directions based on first principle

Ge Schottky diode is the core component of the rectifier circuit in wireless power transfer. By reducing its series resistance, the rectification efficiency of the wireless power transfer can be improved. Ge can be made into a direct band gap semiconductor by alloying with 8% Sn component or 3% Pb component. The electron mobility of direct band gap Ge1-xYx (Sn, Pb) alloy is two to three times that of Ge. High electron mobility will reduce the series resistance of a Schottky diode. Therefore, in recent years, direct band-gap Ge1-xYx (Sn, Pb) alloys for Schottky diodes have attracted much more attention. Using a direct band gap Ge1-xYx (Sn, Pb) alloy to make a Schottky diode requires designing a Schottky junction first. To this end, the first-principle method is used to calculate Ge1-xYx (Sn, Pb) alloys along different directions, which provides a theoretical basis for the subsequent Schottky junction design.

The largest component of faulty star graphs

The minimum size of the largest component of a network with faults is a useful parameter to make a full evaluation of this network and it is helpful for estimating some other parameters in graph theory. In this paper, we focus on discussing the minimum size of the largest component of star graph Sn which contains faulty edges. Specifically, we show that there exists at most one, two, three, four, five vertices beyond the largest component of Sn−F with F⊆E(Sn) and |F|≤2n−5,3n−8,4n−11,5n−15,6n−19 respectively. As applications, we study the g-extra edge connectivity of Sn for 1≤g≤5, and study the strong Menger edge connectivity of Sn−F with F∈E(Sn).