Phosphorus Alloy Research Articles

Precision Manufacturing in China of Replication Mandrels for Ni-Based Monolithic Wolter-I X-ray Mirror Mandrels

The X-ray satellite “Einstein Probe” of the Chinese Academy of Sciences (CAS) was successfully launched on 9 January 2024 at 15:03 Beijing Time from the Xichang Satellite Launch Center in China with a “Long March-2C” rocket. The Einstein Probe is equipped with two scientific X-ray telescopes. One is the Wide-field X-ray Telescope (WXT), which uses lobster-eye optics. The other is the Follow-up X-ray Telescope (FXT), a Wolter-I type telescope. These telescopes are designed to study the universe for high-energy X-rays associated with transient high-energy phenomena. The FXT consists of two modules based on 54 thin X-ray Wolter-I grazing incidence Ni-replicated mirrors produced by the Italian Media Lario company, as contributions from the European Space Agency and the Max Planck Institute for Extraterrestrial Physics (MPE), which also provided the focal-plane detectors. Meanwhile, the Institute of High Energy Physics (IHEP), together with the Harbin Institute of Technology and Xi’an Institute of Optics and Precision Mechanics, has also completed the development and production of the structural and thermal model (STM), qualification model (QM) and flight model (FM) of FXT mirrors for the Einstein Probe (EP) satellites for demonstration purposes. This paper introduces the precision manufacturing adopted in China of Wolter-I X-ray mirror mandrels similar to those used for the EP-FXT payload. Moreover, the adopted electroformed nickel replication process, based on a chemical nickel–phosphorus alloy, is reported. The final results show that the surface of the produced mandrels after demolding and the internal surface of the mirrors have been super polished to the roughness level better than 0.3 nm RMS and the surface accuracy is better than 0.2 μm, and the mirror angular resolution for single mirror shells may be as good as 17.3 arcsec HPD (Half Power Diameter), 198 arcsec W90 (90% Energy Width) @1.49 keV (Al-K line). These results demonstrate the reliability and advancement of the process. As the first efficient X-ray-focusing optics manufacturing chain established in China, we successfully developed the first focusing mirror prototype that could be used for future X-ray satellite payloads.

Tin–Phosphorus Alloy: The Impact of Temperature on Alloy Formation and the Influence of the Dross Amount on the Solder Bath Surface

Tin–Phosphorus Alloy: The Impact of Temperature on Alloy Formation and the Influence of the Dross Amount on the Solder Bath Surface

A study of the wear resistance of carbon fiber composites deposited using an alkaline-based palladium-free electroless plating method

To improve the wear resistance of carbon fibers, we optimized the ratio of the plating solution components and developed a new and economical alkaline-based palladium-free method to evenly coat carbon fibers with nickel–phosphorus alloy. The carbon fibers coated with composites deposited using this method demonstrated enhanced frictional properties. Next, the coating thickness was adjusted and tested, and the effects of coating thickness and surface morphology on the frictional properties of carbon fibers were studied to determine the most suitable coating thickness. The friction coefficient and wear rate of the coated composites were analyzed using a friction and wear testing machine under non-lubricated sliding conditions while controlling the friction duration. The surface morphology, elemental composition and oxidation transfer film morphology of carbon fibers with various coating thicknesses were characterized using field-emission scanning electron microscopy and energy-dispersive X-ray photoelectron spectroscopy. The results showed that the oxidation transfer film substantially prevented the internal fibers from participating in the friction process, and the friction coefficient and wear rate decreased as the uniform coverage area of the transfer film increased. The surface wear mechanism of the carbon fibers was analyzed, and abrasive wear was found to be the main wear mechanism. The findings of this study provide a theoretical and experimental reference for reducing the friction and improving the wear resistance of carbon fibers.

Gate-controlled photoresponse improvement in b-AsP/WSe2 heterostructures with type-I band alignment

As a promising two-dimensional (2D) layered material, black arsenic phosphorus (b-AsP) alloys have received growing attention due to their unique properties and their ability for high-performance broadband photodetection. However, high dark current and slow response speed have already become bottlenecks for further development. Manual vertical van der Waals heterojunctions made of different 2D materials offer opportunities to alleviate such bottlenecks in a simple and low-energy way. The rational design of band alignment can facilitate device performance. In this work, we design and achieve a type-I vertically stacked WSe2/b-As0.084P0.916 device, which exhibits a rectification ratio of 102 along with an unusual backward current as low as 10−12 A. As such, this device can function as an ultrasensitive photodetector, which shows excellent photoresponse properties from the visible to near-infrared region (275–850 nm), with a responsivity of 244 A/W, a specific detectivity of 2.27 × 1012 Jones, and a fast response speed of τrise ≈ 5.1 ms and τdecay ≈ 4 ms. Compared to the dark state, the hole mobility under light stimulation is raised more than ten times (from 1.1 to 12.1 cm2 V−1 s−1), which contributes to numerous excited electron–hole pair transfers from WSe2 to b-As0.084P0.916. The responsivity and detectivity increase by 5 and 3 orders of magnitude, respectively, after applying gate voltage, indicating remarkable gate-controlled properties. These results suggest that the WSe2/b-As0.084P0.916 heterostructure is a promising candidate for future electronic and optoelectronic applications.

Enrichment of hydrogen-oxidizing bacteria using a hybrid biological-inorganic system.

Hybrid biological-inorganic (HBI) systems comprising inorganic water-splitting catalysts and aerobic hydrogen-oxidizing bacteria (HOB) have previously been used for CO2 conversion. In order to identify new biocatalysts for CO2 conversion, the present study used an HBI system to enrich HOB directly from environmental samples. Three sediment samples (from a brackish water pond, a beach, and a tide pool) and two activated sludge samples (from two separate sewage plants) were inoculated into HBI systems using a cobalt phosphorus (Co-P) alloy and cobalt phosphate (CoPi) as inorganic catalysts with a fixed voltage of 2.0V. The gas composition of the reactor headspaces and electric current were monitored. An aliquot of the reactor medium was transferred to a new reactor when significant consumption of H2 and CO2 was detected. This process was repeated twice (with three reactors in operation for each sample) to enrich HOB. Increased biomass concomitant with increased H2 and CO2 consumption was observed in the third reactor, indicating enrichment of HOB. 16S rRNA gene amplicon sequencing demonstrated enrichment of sequences related to HOB (including bacteria from Mycobacterium, Hydrogenophaga, and Xanthobacter genera) over successive sub-cultures. Finally, four different HOB belonging to the Mycobacterium, Hydrogenophaga, Xanthobacter, and Acidovorax genera were isolated from reactor media, representing potential candidates as HBI system biocatalysts.

EFFECT OF UREA IN THE ELECTROLESS BATH ON THE PLATING RATE, PHOSPHORUS CONTENT AND CORROSION RESISTANCE OF THE Ni–P DEPOSITS

Proper selection of bath additives is critical to the plating rate, phosphorus content and corrosion resistance of the nickel–phosphorus (Ni–P) alloy deposits. In this work, electroless Ni–P alloy deposition from an acidic bath using sodium hypophosphite as the reducing agent at relatively low temperatures (30°C and 60°C) was carried out in the presence and absence of urea additives. The effects of different concentrations of urea on plating rate and phosphorus content of the Ni–P deposits were studied. The results showed that the plating rate and the phosphorus content of the Ni–P deposits were largely dependent on the concentration of urea in the bath. The corrosion resistance of the Ni–P deposits was evaluated in aerated 3.5 wt.% sodium chloride (NaCl) solution using potentiodynamic polarization curves. It was found that the corrosion resistance of the deposits obtained from the bath solution containing 1 g/L of urea was the highest. In addition, cyclic voltammetry techniques were used to study the mechanism of electroless Ni–P alloy deposition in the bath. The results revealed that the addition of urea to the bath promoted the concentrations of adsorbed atomic hydrogen and sodium hypophosphite on mild steel surface, which markedly increased the phosphorus content of the Ni–P deposits. This work offers a new way that highlights the relation between the urea additives and phosphorus content.

Drilling fluid adhesion resistance of electroless plating nickel phosphorus (Ni-P) alloy coating deposited on laser-textured surface of bit waterways

The drilling ball phenomenon on polycrystalline diamond compact(PDC) bit seriously restricts the exploitation of oil and gas fields. Wear-resistant Ni-P alloy coating and surface hydrophobic texture are used to solve the problem of ball drilling. Ni-P alloy coating deposited on 42CrMo laser-textured (rectangular, linear and sinusoidal) surface by electroless plating. In the wettability of water-based drilling fluid, the rectangular texture coating with a spacing of 150–200 µm has a maximum contact angle of 133.7°, which is 75.69 % higher than the 42CrMo steel. the anti-mud adhesion and erosion life has also been improved to a certain extent. This research provides important experimental results and theoretical basis for solving the ball drilling problem of PDC bits.

Crystallinity of Co-P coating on microstructure and mechanical properties of Co-Sn intermetallic compounds at Sn-Ag/Co-P/Cu Interface

In advanced microelectronic packaging technology, the interfacial brittleness of Cu/Sn solder joints puts forward higher requirements for high-performance diffusion barriers. Cobalt–Phosphorus (Co-P) alloy coating becomes ideal candidates for its good wettability and diffusion resistance. In this work, for Co-P with different crystallinity, the barrier properties of electrodeposited Co-P coatings as well as the mechanical properties of Co-Sn intermetallic compounds (IMCs) at the Co-P/Sn-Ag interface were investigated. According to the XRD results, the crystallinity of the Co-P coating was directly related to the phosphorus (P) content, and Co-P were classified into three types: crystalline state, mixed state and amorphous state. The morphology, composition, phase characterization, and mechanical properties of the Co-Sn IMCs at the interface were investigated by SEM, EPMA, TEM, and nanoindentation methods, respectively. After 180 °C aging test for 120 h, the thickness of CoSn3 generated at the interface of crystalline Co-4.2 at.% P/Sn-Ag was the smallest among a total of 18 Co-P coatings, where P content ranged from 0.9 at.% to 20.8 at.%, showing the best barrier properties. The hardness of (Co,Cu)Sn3 at the amorphous Co-P/Sn-Ag interface was the lowest (3.2 GPa), which was only 47% of that of Ni3Sn4, exhibiting the lowest brittleness tendency. The mixed crystalline-amorphous Co-P could greatly improve the diffusion barrier properties while sacrificing a small degree of brittleness comparing to the amorphous coatings, and had the potential to become a general-purpose alloy coating. This work could provide a scientific basis for the selection of Co-P barrier layers with excellent barrier properties and mechanical properties leading to different application scenario in electronic packaging.

A modified diamond micro chiseling method for machining large scale retroreflective microstructure on nickel phosphorus alloy

Microstructure surface can produce excellent functions or performances. However, many microstructures have not been applied widely because of high production costs on industrial scale. The fabrication of large scale cube corner array is still a challenge because of the time-consuming problem. To reduce the manufacture cost of large scale cube corner array, a modified diamond micro chiseling (DMC) method is proposed in this paper. By using the modified method, a cube corner array with the size of 200 µm is successfully fabricated on a 10 mm × 12 mm Ni-P alloy substrate. Experimental observations show that the machined microstructure array has a good homogeneity, and the surface roughness of three cube facets is less than Sa 10 nm. This modified method employs an optimized tool path and targeted design of diamond cutting tool to reduce the processing time. Three facets of cube corner can be chiseled in one process step. By utilizing the optimization strategies, the processing time is reduced to 40 h without deterioration of machining surface quality, which is far less than that consumed by the conventional method, i.e. 95 h. This work presents a method to reduce the manufacturing cost of microstructure surface, through which the microstructure processing can be more cost-effective and widely applied in the future.

Advanced Dual-Ion Batteries with High-Capacity Negative Electrodes Incorporating Black Phosphorus.

Dual‐graphite batteries (DGBs), being an all‐graphite‐electrode variation of dual‐ion batteries (DIBs), have attracted great attention in recent years as a possible low‐cost technology for stationary energy storage due to the utilization of inexpensive graphite as a positive electrode (cathode) material. However, DGBs suffer from a low specific energy limited by the capacity of both electrode materials. In this work, a composite of black phosphorus with carbon (BP‐C) is introduced as negative electrode (anode) material for DIB full‐cells for the first time. The electrochemical behavior of the graphite || BP‐C DIB cells is then discussed in the context of DGBs and DIBs using alloying anodes. Mechanistic studies confirm the staging behavior for anion storage in the graphite positive electrode and the formation of lithiated phosphorus alloys in the negative electrode. BP‐C containing full‐cells demonstrate promising electrochemical performance with specific energies of up to 319 Wh kg–1 (related to masses of both electrode active materials) or 155 Wh kg–1 (related to masses of electrode active materials and active salt), and high Coulombic efficiency. This work provides highly relevant insights for the development of advanced high‐energy and safe DIBs incorporating BP‐C and other high‐capacity alloying materials in their anodes.

Micro-Compression Characterization and Thermal Stability of Electrolessly Plated Nickel Phosphorus Alloy

The micro-compression characteristic of an electrolessly plated Ni-P alloy was evaluated in this study. Specimens used in the micro-compression test were micro-pillars having a square cross-section fabricated by focused ion beam system. One side of the square cross-section was varied from 5 to 20 μm and the aspect ratio of the micro-pillars was kept at 2:1 to evaluate the sample size effect on the mechanical property. The as-plated Ni-P alloy was amorphous. The sample size effect commonly observed in mechanical properties of metallic micro-specimens was not obvious for micro-pillars fabricated from the as-plated Ni-P alloy, and all of the micro-pillars showed shear band deformation with the 0.2% yield strength at roughly 2.2 GPa. Heat treatment was conducted to study the influence on the sample size effect. After heat treatment at 300 °C for 2 h, an increase in the strength was observed in micro-pillars with all sizes. In addition, for the heat-treated specimens, the fracture strength increased from 3.1 to 4.7 GPa when cross-section of the micro-pillar decreased from 20 × 20 to 10 × 10 μm2, which revealed the sample size effect.

High-efficiency nitrate electroreduction to ammonia on electrodeposited cobalt-phosphorus alloy film.

Electrocatalytic eight-electron nitrate (NO3-) reduction is a sustainable strategy to degrade NO3- and convert it into high value-added ammonia (NH3) but needs efficient catalysts with high activity and selectivity. Our study shows the use of Ti plate supported cobalt-phosphorus alloy film (Co-P/TP) as a highly active and selective electrocatalyst for ambient NO3--to-NH3 conversion. In 0.2 M Na2SO4 with 200 ppm NO3-, Co-P/TP offers an NH3 yield rate of 416.0 ± 7.2 μg h-1 cm-2 and a high faradaic efficiency of 93.6 ± 3.3% at -0.6 V and -0.3 V vs. reversible hydrogen electrode, respectively, with good durability. Noticeably, a conversion rate of 86.9% is achieved after 10 h bulk electrolysis.

Effect of Secondary Deposition Parameters on the Magnetic Properties of Electrodeposited Cobalt Nickel Phosphorus Alloys

Electrodeposited cobalt nickel phosphorus alloys are characterized by interesting magnetic properties, which motivate their potential applicability in micro-electromagnetic devices like sensors and actuators. CoNiP is suitable for MEMS fabrication due to its relatively high coercivity and maximum magnetic energy product. Moreover, the columnar grain structure typical of electrodeposited layers introduces a high magnetic anisotropy, which is desirable for devices that require high magnetic flux and energy product along a specific direction [1]. In addition to their magnetic properties, CoNiP alloys are also characterized by high hardness, which makes them good candidates for the production of anti-wear coatings, and by good corrosion resistance. Finally, CoNiP coatings show a notable catalytic activity, which can be exploited in water splitting applications [2].One of the most remarkable advantages of using electrodeposition for CoNiP production is the possibility to easily tune magnetic properties by varying deposition parameters. Physical and chemical parameters like bath composition, temperature, pH, presence of additives have a great role on final properties determination [3]. Magnetic behavior can be soft or semi-hard according to the conditions employed. Magnetic properties, however, depend not only on the chemistry of the electrolyte and the primary plating parameters, but also on other secondary deposition aspects. These include, for example, the substrate on which the alloy is plated [4] and its roughness [5]. Furthermore, the application of an external magnetic field during the deposition can influence final properties of the deposited layer. Finally, also the presence of inert particles codeposited within the CoNiP layer can change the magnetic behavior of the coatings. In this context, CoNiP has been poorly characterized in the existing literature.The aim of the present work is to explore the influence of some secondary deposition parameters on CoNiP magnetic properties. In detail, a CoNiP electrolyte was selected and its chemical composition was kept constant during the experimentation. The same was done with the deposition parameters. CoNiP was deposited on different substrates, characterized by different materials (brass, copper, silver) and by different degrees of roughness. The alloy was also codeposited with inert (TiO2) nanoparticles and in presence of an external magnetic field. The influence of these variables on final magnetic properties was investigated with vibrating sample magnetometry (VSM). Surface morphology and phase composition were characterized by mean of SEM and XRD. CoNiP layers were also annealed, and the effect of the heat treatment on magnetic properties was studied.Finally, the observed substrate sensitivity of CoNiP magnetic properties was exploited to introduce a surface magnetic anisotropy in electrodeposited CoNiP layers. Brass substrates were patterned with electrodeposited copper and CoNiP was deposited on top. Magnetic force microscopy (MFM) was employed to characterize the result, evidencing differences in magnetic properties between the zones where CoNiP was plated on brass and the zones where CoNiP was plated on electrodeposited copper. The final result was a magnetically patterned CoNiP coating, which may potentially find application in microelectronics and sensors production.[1] C. J. Hsiao et al., AIP Advances 7, 056210 (2017)[2] A. Han et al., J. Mater. Chem. A 4, 10195 (2016)[3] P. Cojocaru et al., Trans. Inst. Met. Fin. 89(4), 194 (2011)[4] E. I. Manimaran et al., J. Mater. Sci. Mater. Electron. 26, 9821 (2015)[5] S. J. Steinmuller et al., J. Appl. Phys. 101, 09D113 (2007)

Tailoring of elastic, optoelectronic, and thermal properties of antimony doped indium phosphorus alloys for optoelectronic applications

The structural, elastic, mechanical, optoelectronic, and thermodynamics properties of InP, InSb, and their mixed ternary alloys, InP1-xSbx, in their zinc blende structure for 0 ≤ x ≤ 1, are studied. The “full potential linearized augmented plane wave (FP-LAPW) method framed within density functional theory (DFT)" as realized in WIEN2k computational code is employed for all calculations. The results of elastic constants for simulated structures of InP1-xSbx alloys are the first time computed in this study. The results of the elastic constants showed that the InP1-xSbx alloys, for all compositions of x, are brittle and mechanically stable above and beyond showing the strong anisotropic character as well. On the other hand, the obtained results of InP1-xSbx for lattice parameters, bulk modulus, and band gap energy exhibit their nonlinear character. Also, the optical properties are determined at the level of the mBJ scheme for an energy range from 0 to 40eV. However, the “quasi-harmonic Debye model” is used to investigate the thermodynamics properties for example Debye temperature, specific heat, entropy, and their dependence on pressure, and the temperature is also analysed for the mentioned alloys. Our computed results for optical band gap and absorption coefficients expose these alloys as suitable candidate materials for optoelectronics applications in the infrared as well as in the visible region.

Physicochemical Model of Selection of Complex Compounds for Electroless Metal Plating

A physicochemical model of the choice of a ligand for the electroless deposition of metal–phosphorus alloys is proposed based on determining the conditions for electrochemical reactions that cause the formation of the alloy and minimizing possible side reactions that impede the quality of the deposition process. Based on the physicochemical model, the optimal range of values of the stability constants and pH was determined for electroless nickel plating. It is shown that, for the pH range 7–9, which corresponds to the maximum deposition rates, stability constants take values from 5 to 10; carrying out the process in more alkaline solutions requires the use of more stable complexes. The predictive ability of the model is confirmed by experimental studies of the process of electroless nickel plating from solutions of various ligand compositions.

Surface Energy of Black Phosphorus Alloys with Arsenic

AbstractBlack phosphorus belongs to the most intensively studied two‐dimensional materials with many unusual properties. It is capable of forming solid solutions with arsenic, which allows continual tuning of its properties. The vapour phase transport method was used for effective synthesis of black phosphorus and its alloys with arsenic of defined composition using SnI4/Sn mineralising agent. The incorporation of arsenic up to over 50 at.% was confirmed by X‐ray photoelectron spectroscopy. Structural changes were observed by X‐ray diffraction and Raman spectroscopy. Density functional theory calculations were used to calculate the change of lattice parameters due to alloying, to model Raman activity of the bP−As alloy and to estimate the surface energy of the alloy. The surface properties of black phosphorus and its alloys with arsenic were measured by inverse gas chromatography. Although the differences of surface energy between black phosphorus and its alloys were relatively low, the surface energy profiles were unusually flat, indicating a sparsity of high‐energy sites on the surface of the alloys.

Black phosphorus–arsenic alloys for lithium ion batteries

Phosphorus and arsenic belong to the 5th group of elements – so-called pnictogens. These materials are among the most intensively studied nanomaterials with layered structure. In this contribution we report the synthesis of arsenic – black phosphorus alloys. Two samples with various black phosphorus and arsenic content together with pure black phosphorus were exfoliated using shear force milling. Extensive analyses have revealed the successful synthesis of AsP alloys with good crystallinity and composition close to that of the intended value. Testing these materials for lithium ion batteries (LIBs) shows that there is a huge capacity loss after the initial charge/discharge cycles. Such a drop was attributed to a delithiation of the lithium rich phase and a loss of proper electrical contact. After the initial capacity loss, the Coulombic efficiencies in the subsequent cycles reached 90–99%. Moreover, both of the alloys exhibited higher capacity than pure black phosphorus sample, indicating that alloying with arsenic is an advantageous technique. The results of this work show the fundamental charge storage capabilities of AsP alloys a can serve as a starting point for the synthesis of advanced materials based on AsP alloys.

Electrochemical Synthesis of Ni-Cu-P Alloy As an Efficient Water Splitting Electrocatalyst

In recent years, global warming due to increased carbon dioxide emissions has emerged as the largest environmental problem in the world. Hydrogen has been recognized as an eco-friendly energy source that has no carbon dioxide emission, helps to reduce fine dust, thus attracting attention as an eco-friendly energy source which will be commercialized in the future [1,2]. Although the use of hydrogen energy does not emit air pollutants such as carbon dioxide, fossil fuels are currently used in the process of hydrogen production, so that a large amount of carbon dioxide and pollutants are emitted, making hydrogen unlikely to be a truly environmentally friendly energy source. Hydrogen production by water splitting is considered as a possible method to produce a large amount of hydrogen without the emission of pollutants. Water splitting is divided into two reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The most efficiently known catalysts in each reaction are platinum and iridium, respectively, and both are very expensive noble metal catalysts. High cost of the catalysts has been a major obstacle to the application of massive water electrolysis. In recent years, numerous attempts have been made to replace precious metal catalysts with relatively inexpensive transition metals. Nickel and its alloys are widely used as an alternative material for efficient water splitting, owing to their excellent activity and stability [3]. In this study, we developed a technology to make cheap alloy catalysts by electrodeposition and electroless plating with nickel and copper as alloying elements, and apply this catalyst to both oxygen generation and hydrogen generation reaction under alkaline solution. Compared with the use of nickel single metal catalysts, the electronic structure of nickel can be controlled when alloys are synthesized. The increase or decrease of the activity depending on the alloy ratio is observed due to the change of the electronic structure, so that the activity can be expected to be increased through the optimization. Copper has been suggested as one of alloying candidate in this work. Earlier, interaction between nickel and copper in solid solution has been reported with various XRD and XPS studies, which eventually confirmed that catalytic activity change of solid solution is related to the degree of alloying [4,5]. According to previous studies, binding energy of Ni has shifted with addition of copper. Many studies of metal-phosphorous based catalysts already found that phosphorous content causes enhancement of their activities by inducing partial positive charge on active metal centres [6]. Electroplating enables synthesis of metal and metal alloys with relatively low cost. High temperature and high pressure processes are not required for the production of alloys, and electrodeposited alloys are highly compatible for application as electrochemical catalysts. Electroless nickel is a widely used, characterized by excellent uniformity and corrosion resistance. Plating using an autocatalytic reaction enables uniform plating since the precipitated metal acts as a catalyst. If nickel plating using sodium hypophosphite (NaH2PO2) is used, phosphorus alloy is naturally deposited depending on the plating condition, and copper can be added to the solution as an additional alloying element. Most of reported water splitting catalysts have given emphasis on nanostructure holding high surface area. These catalysts usually assume the form of powders including nanostructures, which may require conductive adhesive polymers to be applied on electrode surface. Such process may reduce active surface area and electrical conductivity considerably, resulting in decreased catalytic activity, while electrochemical plating enables production of alloys with excellent adhesion. Through previous research, it has been confirmed that the electrodeposited nickel-copper-phosphorus ternary alloy exhibits excellent water oxidation activity as compared with the nickel-phosphorus alloy, which is already known as promising OER electrocatalyst [7]. This was extended to overall water splitting of the nickel-copper-phosphorus catalyst. Carbon fiber paper (CF) was used as a template of the deposition, which has high surface area compared to film-type substrate. The catalyst on CFP is also adaptable on gas diffusion layer (GDL) on fuel cell device applications. Reference S. Chu and A. Majumdar, Nature 488, 294 (2012).S. Anantharaj, S.R. Ede, K. Sakthikumar, K. Karthick, S. Mishra and S. Kundu, ACS Catal. 6, 8069 (2016).A.J. Bard and M.A. Fox, Acc. Chem. Res. 28, 141 (1995).A.R. Nagahash, T.H. Etsell and S. Xu, Chem. Mater. 18, 2480 (2006).S. Hufner, G. K. Wertheim and J. H. Wernick, Phys. Rev. B, 8, 4511 (1973).L. Stern, L. Feng, F. Song and X. Hu, Energy Environ. Sci. 8, 2347 (2015).B.K. Kim, S.-K. Kim, S. K. Cho and J. J. Kim, Appl. Catal. B, 237, 409 (2018).

Influence of Characteristics of Nickel Complex Compounds on the Rate of Chemical Deposition and Composition of Nickel–Phosphorus Alloy

The influence of characteristics of ligands and nickel complex compounds on the rate of the autocatalytic (chemical) deposition of nickel–phosphorus coating and the phosphorus content is considered. It has been established that the charge and complex of the ligand have the highest effect on the rate of process, and charge number and stability of the complex ion have the highest effect on the content of phosphorus in the coating. Mathematical models describing the relationship between the deposition rate, the composition of coatings, and the corresponding ligand parameters are obtained. Recommendations for the selection of the ligand composition of solutions for the chemical deposition of nickel–phosphorus alloy are proposed.

Refining of high-phosphorus manganese alloys, which are formed during electrometallurgical Dephosphoration of manganese ore

Goal. Creation of the most rational way of dephosphorization of manganese alloys. Method. Thermodynamic calculations to establish the preference of the reactions during dephosphorization. Computer modeling of the influence of the charge composition on the process of reducing the phosphorus content. Experimental studies in the laboratory during a two-stage processing of high phosphorus metal. Results. The results of computer modeling and experimental study of the refining process of manganese alloy with high content of silicon and phosphorus indicate the feasibility of using the experimental slag-forming mixture based on Na4SiO4. Comparisons of the calculated data with the results of experimental melting show that there are differences in their values. These differences are due to the fact that in real conditions the thermo-dynamic forecast does not always coincide with the kinetics of the real process. The obtained experimental data indicate that the analyzed system achieves a state of dynamic equilibrium in contrast to the data of thermodynamic calculations by the program, which does not take into account the kinetics of the real process and the assumptions made in the simulation. Scientific novelty. The results of experimental studies have shown that the adopted physico-chemical features of the one-stage method of refining the alloy from silicon and phosphorus at a temperature of ~ 1350oC, provide protection of manganese from oxidation with the use of Na4SiO4. Practical significance. Therefore, it is advisable to implement the developed scheme of dephosphorization of the accompanying manganese alloy, which is formed during the production of low phosphorus slag, in industrial conditions. Given that the limiting link in the refining process is the oxidation reaction of the phosphorus alloy due to the interaction with Fe2O3, it is advisable to use forced mixing of the metal and the alloy by purging with neutral gas. Key words: phosphorus, manganese ore, concomitant manganese alloy, low phosphorus slag, dephosphorization,