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The copper electroless deposition process is highly sensitive, since it works at high pH (>12). To ensure the stability of the bath, stabilisers are added, which reduces the deposition rate. In the current study, additives were used to improve the plating rate. The plating rate of electroless plating of copper on a metal surface was examined with the addition of organic acids (mono, di and tri basic) in the presence of a stabiliser, thiourea. The investigation was carried out utilising gravimetric studies, cyclic voltammetric studies and crystal orientation by X-ray diffraction method (XRD), and surface morphology by scanning electron microscopy (SEM). The investigation shows that organic acids can be used as an additive to improve the plating rate in the presence of stabilisers without affecting the stability of the bath and the quality of deposits. [ABSTRACT FROM AUTHOR]

In this paper, alumina-reinforced copper-based composite materials were prepared by using the electroless plating method to coat copper powder with a layer of silver and then combining the solution sol method and powder metallurgy method. The results show that recrystallized structures and twins appear in composite materials after high-temperature sintering. As the sintering temperature increases, the ratio of recrystallized structures and twins gradually decreases, and straight coherent Σ 3 annealing twins appear in the structure, the number of high-angle grain boundaries decreased, the number of small-angle grain boundaries continues to increase, the average grain size increased from 3.89 to 4.83 μ m, the tensile strength increased from 156 MPa to 167.5 MPa, the maximum elongation was 9.4%, and the density increased from 6.81 g/cm3 increased to 7.62 g/cm3, the porosity dropped from 13.3% to 5.5%, the conductivity increased from 60.3% IACS to 73.2% IACS, the maximum hardness value was 68.71 HV, the best performance of the composite was achieved by sintering at 900°C with the tensile strength and elongation are 163 MPa and 9%, respectively, the conductivity is 68.9% IACS, and the density is 7.35 g/cm3. Its fracture surface shows mostly ductile features. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: The small size of the nanoparticles used to obtain high surface area photocatalysts makes their removal from solution difficult. Producing photocatalysts on substrates would alleviate this limitation. Adding heterojunctions to photocatalysts, for example, TiO 2 /Ag, could improve photocatalytic performance due to Schottky junction formation and introduce antibacterial properties. Experiments: TiO 2 nanorod arrays were synthesised on a substrate via a hydrothermal approach, on which Ag nanoparticles were deposited using an electroless plating technique with varied deposition times and metal precursor concentrations. Photocatalytic performance was evaluated by monitoring Rhodamine B (RhB) degradation under ultraviolet light and antibacterial properties of the films tested using Methicillin-resistant Staphylococcus aureus. Findings: The Ag nanoparticle content was controlled by the Ag deposition process. The TiO 2 /Ag nanorod array containing 6.6 atomic% Ag as nanoparticles of ∼ 25 nm in diameter degraded 88 % of the RhB in 6 h compared to 54 % degradation for bare TiO 2 nanorods under the same reaction conditions. Decreased photoluminescence with heterojunction formation would indicate electron transfer from the TiO 2 into the Ag nanoparticles, thereby reducing charge carrier recombination. The antibacterial test conducted in the dark revealed enhanced performance for the TiO 2 /Ag sample compared to TiO 2 nanorods against Methicillin-resistant Staphylococcus aureus after 16 h exposure with a death rate of 84 %. [ABSTRACT FROM AUTHOR]

Metal electrodes of crystalline silicon solar cells need to possess good photoelectric conversion properties and play a critical role in converting solar energy into electrical energy, making it particularly important to obtain highly conducive, cost-effective and chemically stable materials. This paper prepared uniformly silver-coated copper powders (Cu@Ag) via electroless plating and a conductive film with low sheet resistance by air oxidation combined with hydrogen reduction sintering (jointly referred to as oxidation–reduction sintering). In addition, the densification mechanism of the Cu@Ag conductive film during sintering was revealed. Results showed that oxidation–reduction sintering promoted the diffusion between Cu and Ag, enhancing the plastic flow of phases and improving the densification of the conductive film. Moreover, the densification of the conducive films was further improved by designing multiple layers. The sheet resistance of the four-layer Cu@Ag conductive film was reduced to 1.5 mΩ/□ at 700 °C, while that of the four-layer Cu@Ag conductive film increased by only 0.6 mΩ/□ at 200 °C after eight days, much more stable than Cu film. This work demonstrates the tremendous potential of oxidation-resistant Cu@Ag conductive pastes in low-cost photovoltaic cells, electronics, and other commercial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Developing cost-effective and highly efficient electrodes for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is crucial, particularly for alkaline OER and HER. Herein, electroless plating of iron-nickel–cobalt (Fe–Ni–Co) electrocatalyst on a flexible polyacrylonitrile (PAN)-based carbon cloth (CC) was performed to synthesize a free-standing catalytic electrode for bifunctional electrocatalysts. The three-dimensional porous backbone of PAN-based CC and the synergistic effect between Fe-Ni-Co and corresponding hydroxides result in outstanding OER and HER activities, that is low overpotentials of 230 and 150 mV at 10 mA cm−2 and Tafel slopes of 63 and 57.1 mV dec–1, respectively. Additionally, a complete alkaline electrolyzer was constructed using Fe-Ni-Co plated PAN-based CC as both the cathode and anode. When operated at 10 mA cm−2, this setup enabled efficient water splitting at a low potential of 1.57 V. This study provides new opportunities for the development of advanced Fe-Ni-Co electrocatalyst with superior bifunctional OER and HER performance and cost-effectiveness that are suitable for integration into PAN-based CC via electroless plating. [ABSTRACT FROM AUTHOR]

Efficient and corrosion resistant 15 %PANI-NiB@Ti catalytic electrode was rapidly prepared by one-step mild electroless plating, which maintains its hydrogen evolution and morphological integrity in harsh environments. [Display omitted] • Highly efficient 15 %PANI-NiB@Ti is prepared via one step mild electroless plating method. • The doping of polyaniline significantly reduces the cracking phenomenon and improves the HER evolution performance of the electrode. • Excellent corrosion resistance enables the electrode to tolerate the harsh environment such as high temperature. The economic and reasonable design of highly stable and corrosion-resistant electrodes is fundamental to achieving the industrial-scale hydrogen productions via water electrolysis, but electrodes' premature failures are often caused by corrosion and stress damage. Therefore, these challenges are successfully solved by utilizing conductive and crack-resistant polyaniline "stabilizer" with a mild chemical plating process to construct the catalytic electrode on a titanium substrate (15 %PANI-NiB@Ti) in the present work. The 15 %PANI-NiB@Ti catalytic electrodes have been in continuous operation for 350 h at the current density of 200 mA cm−2 with the high efficiency of 98.4 % in a 323.15 K environment. With the high economy and universality, the catalytic electrodes have good catalytic performance and reliability in the extreme industrial environments, such as high temperature, air, and high current density. Except for the above advantages, the 15 %PANI-NiB@Ti catalytic electrodes also have good cracking resistance, which provides a novel and feasible approach to the industrial application of transition metal catalytic electrodes. [ABSTRACT FROM AUTHOR]

Electroless nickel–phosphorus (Ni–P) plating is a widely used surface treatment method due to its excellent corrosion and wear resistance properties. However, the inertness of copper to hypophosphite oxidation necessitates a palladium activation process for the preparation of Ni–P coating on copper. In this study, a convenient approach is presented for the deposition of a cobalt layer on copper using galvanic replacement, facilitated by the special complexing ability of iodide. The results demonstrated that the actual potential of copper could be adjusted to be lower than that of cobalt in a solution containing 8 mol L−1 NaI, enabling the deposition of a cobalt layer on copper in 15 min at 90 °C. Furthermore, the deposition rate of the cobalt layer was found to increase with the concentration of CoCl2 in the NaI solution. Importantly, the Ni–P coating obtained through cobalt layer activation from either acidic or alkaline plating solution exhibited morphology, structure, corrosion resistance, and tribological performance similar to the Ni–P coating obtained using the common palladium activation. The Ni–P coatings obtained through cobalt and palladium layer activation from alkaline plating solution had a larger thickness than the Ni–P coating obtained from acidic plating solution. Therefore, the cobalt layer prepared on copper through galvanic replacement may serve as a viable alternative to palladium for activating electroless Ni–P plating. [ABSTRACT FROM AUTHOR]

Hydrogen embrittlement affected by three types of plating (low-P and high-P types electroless Ni-P plating and electrolytic zinc plating) was investigated by means of slow-strain-rate three-point bending test on three aluminum alloys (2017-T3, 6061-T6 and 7075-T651). Hydrogen generated by the Ni-P and zinc plating was absorbed in the aluminum alloy substrates, and the trap sites in the aluminum alloy substrates for the absorbed hydrogen differed between Ni-P and zinc plating. Hydrogen embrittlement was able to be evaluated by the three-point bending tests on plated aluminum alloys. Zinc plating did not cause embrittlement for all the alloys, but Ni-P plating induced embrittlement only for the 6061-T6 aluminum alloy. The result of embrittlement of the Ni-P plated 6061-T6 aluminum alloy corresponds to the highest amount of hydrogen desorbed below 240°C than the other alloys. [ABSTRACT FROM AUTHOR]

The electrical contact and tribological performance of contacts are critical for the reliable transmission of electric power and signals. In this study, a nickel layer was applied as an underlayer at the interface, and the effects of its thickness and plating process on the electrical and tribological properties were systematically investigated. Results showed that the coefficient of friction (COF) was reduced due to the nickel layer. The wear loss significantly decreased as the nickel layer thickness increased from 0.5 μm to 2 μm. This is primarily due to the nickel layer reducing adhesive wear. Additionally, the electrical contact resistance (ECR) increased as the top coating was worn out, owing to a reduction in the effective conductive area. Furthermore, ECR, COF, and wear rate were further reduced when the nickel layer was deposited using electroless plating compared with electroplating. In conclusion, the wear resistance of electrical contacts can be improved by a thicker nickel layer or electroless plating. This study provides a theoretical basis for understanding the role of the nickel layer in improving sliding electrical contact and wear behaviors. [ABSTRACT FROM AUTHOR]

Short carbon fiber reinforced aluminum matrix composites exhibit suitable thermal conductivity and desirable coefficient of thermal expansion for electronic packaging applications. The interfacial bonding characteristics between carbon fibers and aluminum matrix play a crucial role in determining the performance of the composites. In the present study, the surface modification of carbon fibers and optimization of fabrication processing parameters were used to ameliorate the interface bonding and improve the properties of carbon fiber/Al composites. The electroless plating method was employed to deposit a nickel coating on the surface of carbon fibers. Aluminum matrix composites reinforced with 20∼50 vol.% uncoated or nickel-coated carbon fibers were fabricated by vacuum hot pressing technique. The microstructures, interface structures, relative density and thermal conductivity of the composites were systematically investigated. The results indicated that carbon fiber/Al composites with relatively high density of 98.9% and acceptable thermal conductivity of 218.1 W·m−1 K−1, as potential candidates for electronic packaging applications, were successfully fabricated. Through the application of nickel coating, the interfacial thermal resistance was effectively reduced by one order of magnitude derived from the experimental calculations using Maxwell-Garnett effective medium approach as a result of improved interface bonding. [ABSTRACT FROM AUTHOR]

Background/Objectives: Focused ultrasound has advantages as an external stimulus for drug delivery as it is non-invasive, has high precision and can penetrate deep into tissues. Here, we report a gold-plated alginate (ALG) hydrogel system that retains highly water-soluble small-molecule fluorescein for sharp off/on release after ultrasound exposure. Methods: The ALG is crosslinked into beads with calcium chloride and layered with a polycation to adjust the surface charge for the adsorption of catalytic platinum nanoparticles (Pt NPs). The coated bead is subject to electroless plating, forming a gold shell. Ultrasound is applied to the gold-plated ALG beads and the release of fluorescein with or without ultrasound stimulation is quantified. Results: Polyethylenimine (PEI), not poly-L-lysine (PLL), is able to facilitate Pt NP adsorption. Gold shell thickness is proportional to the duration of electroless plating and can be controlled. Gold-plated ALG beads are impermeable to the fluorescein cargo and have nearly zero leakage. Exposure to focused ultrasound initiated the release of fluorescein with full release achieved after 72 h. Conclusions: The gold-plated ALG hydrogel is a new material platform that can retain highly water-soluble molecules with a sharp off/on release initiated by focused ultrasound. [ABSTRACT FROM AUTHOR]

In recent years, the growing need for materials that have high thermal resistance, non-flammability, high radioactive resistance and durability is the reason for the development of new technologies for electroless metallisation of glasses. The most important operation is surface roughening, which is usually carried out in etching solutions containing HF acid, which is harmful to the environment and to health and safety at work. In this regard, the aim of the present research is the creation of an environmentally friendly technology for electroless metallisation of glasses. Тhe samples were pre-treated in two ways: one group was covered with a thin polymer film (Plastik 70 special glue or epoxy resin, thinned with dimethylformamide), and the other was degreased and treated with a solution of (3 aminopropyl) trimethoxysilane (APTS) at different concentrations and under different conditions. All samples were activated with a colloidal activator, after which copper or nickel-phosphorus coatings were deposited by electroless plating. [ABSTRACT FROM AUTHOR]

The porous Ta membrane was prepared on the surface of Ta foils by spraying and sintering. Subsequently, the Pd/porousTa/Ta composite membrane was prepared by electroless Pd plating processes using the porous Ta/Ta as the composite substrate. The effect of sintering temperature on the morphology of porous tantalum films was studied, and the growth behavior of Pd films was analyzed. In the results, the sintering temperature has a significant impact on the structure of porous Ta membrane. The porous Ta membrane with the well-developed sintering neck can be obtained by sintering at 1700 ℃ for 2 h. The electroless plating time has a significant effect on the Pd membrane on the surface of porous Ta membrane. Moreover, due to the complex surface structure of porous Ta membrane, it is difficult to obtain the uniform and dense Pd membrane on the surface of porous Ta membrane.

Natural fibre-reinforced polymer composites have been most widely used in automotive, aerospace, and structural products in recent years. The synthesis and analysis of mechanical properties of bamboo fibre with polyester matrix nanocomposites produced with titanium oxide nanoparticles are the focus of this research. The electroless plating process was used to prepare bamboo fibre samples that were both uncoated and coated with nickel-phosphorus. These properties were studied both without coating and with coated bamboo fibre content of 4.5, 9, 13.5, and 18 wt. % and nanoparticle weight content of 0.5, 1, 1.5, and 2%. The x-ray diffractometer, field emission scanning electron microscope, and transmission electron microscope were used to investigate the structural and morphological characteristics of polyester matrix composites. Coated bamboo fibre with 13.5 wt.% and 1.5 wt.% titanium oxide. As a result, it can be concluded that the mechanical properties of a polyester matrix-reinforced coated bamboo fibre with nanoparticles have excellent bonding when compared to those of a polyester matrix-reinforced nanocomposite without coated bamboo fibre. [ABSTRACT FROM AUTHOR]

The electrolysis of water is one of low-cost green hydrogen production technologies. The main challenge regarding this technology is designing and developing low-cost and high-activity catalysts. Herein, we present a strategy to fabricate flexible electrocatalysts based on nickel–iron (NiFe) alloy coatings. NiFe coatings were plated on the flexible copper-coated polyimide surface (Cu/PI) using the low-cost and straightforward electroless metal-plating method, with morpholine borane as a reducing agent. It was found that Ni90Fe10, Ni80Fe20, Ni60Fe40, and Ni30Fe70 coatings were deposited on the Cu/PI surface; then, the concentration of Fe2+ in the plating solution was 0.5, 1, 5, and 10 mM, respectively. The morphology, structure, and composition of NixFey/Cu/PI catalysts have been examined using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and inductively coupled plasma–optical emission spectroscopy (ICP-OES), whereas their activity has been investigated for hydrogen evolution (HER) and oxygen evolution (OER) reactions in 1 M KOH using linear sweep voltammetry (LSVs). It was found that the Ni80Fe20/Cu/PI catalyst exhibited the lowest overpotential value of −202.7 mV for the HER, obtaining a current density of 10 mA cm−2 compared to Ni90Fe10/Cu/PI (−211.9 mV), Ni60Fe40/Cu/PI (−276.3 mV), Ni30Fe70/Cu/PI (−278.4 mV), and Ni (−303.4 mV). On the other hand, the lowest OER overpotential (344.7 mV) was observed for the Ni60Fe40/Cu/PI catalyst, obtaining a current density of 10 mA cm−2 compared to the Ni35Fe65 (369.9 mV), Ni80Fe20 (450.2 mV), and Ni90Fe10 (454.2 mV) coatings, and Ni (532.1 mV). The developed Ni60Fe40/Cu/PI catalyst exhibit a cell potential of 1.85 V at 10 mA cm−2. The obtained catalysts seem to be suitable flexible catalysts for HER and OER in alkaline media. [ABSTRACT FROM AUTHOR]

A variety of NiP-TiC-SiC nanocomposite coatings were deposited to acrylonitrile–butadiene–styrene (ABS) substrates at varying plating periods and bath temperatures using electroless plating. A field emission scanning electron microscope (FESEM) demonstrates the production of various coating morphologies. Morphology analysis of the deposit coatings shows homogenous, compact, and nodular structured coatings free of any apparent defects in most deposition conditions, except at extra high-temperature deposition baths, some gas bubbles under the coating layers were seen. The patterns of X-ray diffraction (XRD) illustrate nickel peaks at 44.5 which relates to Ni (111). Energy-dispersive X-ray spectroscopy (EDX) data show that the coating's main constituents are nickel, phosphorus, and nanoparticles. According to the results of the contact angle test, the potentiodynamic polarization, and the impedance spectroscopy (EIS) tests conducted in (3.5%) of NaCl by weight at (25 °C), the nanocomposite coating that was created at 90 min and 75 °C exhibited the best hydrophobic qualities and corrosion resistance. The coating formed at 30 min and 75 °C illustrates the best hardness value. The adhesion force was calculated using the ASTM D 3359 method (B). The findings demonstrate that the coating made under the following deposition conditions, 30 min at 75 °C, 30 min at 95 °C, and 90 min at 75 °C, produces the best bonding strength between the coating and ABS substrate (standard classification 5B); however, the complete gas bubble rejection process from the substrate is rendered difficult by deposition times longer than 30 min in a bath over 85 °C, which decreases the adhesion between NiP-TiC-SiC and the acrylonitrile–butadiene–styrene substrate. The wear rate shows a direct relationship with the coefficient of friction rather than hardness, and the coated prepared at 90 min at 75 °C offers a lower wear rate and coefficient of friction. [ABSTRACT FROM AUTHOR]

The Bi 0.7 Sr 0.3 FeO 3-δ (BSFO)-Ag composite cathode is prepared by modifying BSFO with in-situ chemical plating of Ag. The plated Ag effectively reduces the polarization resistance (R p) of BSFO. At the Ag loading of 20 wt%, the optimized R p of BSFO at 650 °C in air condition is 0.35 Ω cm2, which is only 18.6 % of that of BSFO cathode (1.88 Ω cm2). The electrochemical performance improvement is primarily attributed to the low oxygen adsorption energy (E ads) domain at the interfaces of BSFO-Ag, as indicated by the first-principles calculations (E ads , −0.81eV). Thus, the addition of Ag changes the cathodic reaction rate control step from the molecular oxygen on the cathode surface adsorption and diffusion to charge transfer on the cathode. The maximum power density (P max) of the prepared single cell at 650 °C is 450.98 mW cm−2 using H 2 (∼3 vol% H 2 O) as fuels. The open-circuit voltage (OCV) does not decay significantly (around 0.66 V) after 50 h at the current density of 400 mA cm−2, showing good long-term stability. [ABSTRACT FROM AUTHOR]

Ionic polymer-metal composite (IPMC) sensors were fabricated and investigated for quantifying impact energy in sports applications. Nafion membranes were roughened and electroless plated with gold-platinum electrodes to form IPMCs. When subjected to impacts of varying energies, the IPMCs generated transient voltage spikes whose peak amplitudes and slopes showed exponential relationships with the impact energies. Empirical models were developed correlating the IPMC voltage response features to the impact energies, achieving measurement accuracy within ±10 % RMS error over the tested dynamic range from 0.005 J to 1 J. The IPMC voltage profile was found to depend primarily on the impact energy and resultant strain rate, rather than impactor properties or contact geometry. Proper calibration procedures for each IPMC sensor before deployment were required to account for device-to-device variations. The results demonstrate the potential of IPMC sensors for continuous monitoring of athletes' impacts during sports activities. Further optimization is needed to improve the robustness, repeatability, and stability of the IPMC sensors under realistic sports conditions for reliable field performance. [ABSTRACT FROM AUTHOR]

Current collector (CC) is an indispensable constituent in lithium‐ion battery (LIB). It plays an important role in supporting electrode materials and conducting electrons between the electrode materials and the external circuit. However, the density of metal CC is high and it hinders the lightweight development of LIB. In this work, lightweight three‐dimensional (3D) CC was designed and prepared via a facile electroless plating method. The 3D copper‐plated polyimide CC has a low areal density. The 3D structure of Cu‐PI CC 2 can facilitate Li+ transfer between electrode materials and electrolyte owing to electrolyte can permeate through electrode. Moreover, the lithium titanate anode assembled with the 3D copper‐plated polyimide Cu‐PI CC 2 exhibited enhanced cycling and rate performance. [ABSTRACT FROM AUTHOR]

Lawsonia inermis Linn Leaf extract has been evaluated in alkaline solutions for its influence on electroless Ni–P alloy deposition on mild steel. During electroless plating, the effect of experimental processing conditions on deposition rate is investigated. Bath compositions and operational parameters have been optimized. The findings indicate that increasing the volume of additives from 0.5mL to 5mL improves the inclusion rate of electroless Ni–P alloy coating. In the absence of a complexing agent, additive Lawsone exhibits additional structural features and phases. The deposition rate and the corrosion rate of the Ni–P deposits were estimated, respectively, from the weight loss after a period of time. It is recommended to replace sodium citrate with Lawsone. Lawsone’s effect acting as a complexing agent on Ni–P electroless coating was explored utilizing SEM, EDAX, AFM, FTIR, and XRD, as well as corrosion investigations. Polarization and electrochemical impedance spectroscopy are used to assess the corrosion efficiency. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the growth mechanism and tribological behavior of electroless Ni-P plating with ultrasonic assistance on TC4 titanium alloy substrate pretreated by zincating and alkaline pre-plating process. The morphology, composition and structure of zincating, pre-plating and electroless Ni-P plating were studied to analyze its growth mechanism. The tribological behavior of electroless Ni-P plating at room temperature was investigated. The results showed that the electroless Ni-P plating had a typical cauliflower-like morphology and microcrystalline structure characteristic. And the morphology of the Ni-P plating under the action of ultrasonic was uniform, compact and smooth. Compared with the TC4 substrate, the friction coefficient and the wear scar width of the plating were reduced by approximately 35 and 70%, indicating that the Ni-P plating improved the wear resistance of TC4. The wear mechanism of the Ni-P plating was adhesive wear under the dominant of plastic deformation, and slightly abrasive wear, while the wear mechanism of TC4 was dominated by adhesive wear, accompanied by abrasive wear and oxidative wear. The ultrasonic cavitation promoted the elemental interdiffusion between the substrate and Ni-P plating resulting in the formation of the diffusion layer. The ultrasonic cavitation and mass transfer effects improve the activity of the deposition surface and the generation of atomic hydrogen, and promote the nucleation and growth of nickel on the deposition surface, as well as the diffusion of Ni2+ and H2PO2− to the deposition surface. The growth rate of the Ni-P cell-like structures in the parallel direction is greater than in the perpendicular direction. The Ni-P plating grows in a layered manner, and the growth mechanism is the heterogeneous nucleation growth mechanism. [ABSTRACT FROM AUTHOR]

In this study, wettability was employed to evaluate the effect of alkali activation by NaOH on different fly ash (FA) particle sizes. The results indicated that the surface wettability of FA particles with 13.8 μm increased from 0.025 g2/s to 0.034 g2/s after activation by the NaOH solution, which is suitable for silane modification and electroless plating. X-ray photoelectron spectroscopy (XPS) was used to analyze whether three kinds of silane coupling agents coated on FA surfaces could detect the chemical bonds between silane coupling agents coated on the FA surface and silver layers by shortening the plating time. The XPS results demonstrated that N-Ag coordination bonds can be detected by reducing silver plating time to 2 min for Ag-plated FA modified by N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (KH792). However, there were no chemical bonds detected for Ag-plated FA modified by γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560) and methyltrimethoxysilane (MTMS), even when the satellite peak of Ag disappeared after plating for 80 s. The SEM showed that Ag particles agglomerated on FA surfaces, and even a bare surface was found after modification by KH560 and MTMS, which further proved no chemical bonds between silver layers and the silane coupling agents. [ABSTRACT FROM AUTHOR]

In this study, the role of MgB2 in composite coatings is pivotal. Electroless Ni–B plating, a current‐free chemical reduction process, deposits nickel–boron coatings. Other than MgB2, reinforcements like SiC, B4C, and so forth are used with Ni–B coatings for improved properties. The research focuses on Ni–B/MgB2 coatings on AISI 4140 steel using electroless deposition and annealing at different temperatures. Initially, the coating appears dense and amorphous, transforming into worm‐like structures through crystallization with MgB2. Higher annealing temperatures lead to brush‐like, feathery, and oyster mushroom structures, forming crystalline nickel boron compounds and oxide phases due to synergy. Interestingly, the newly introduced phases disrupt friction patterns nonlinearly, which is linked to MgB2's ceramic nature and reinforcement quantity. Conversely, incorporating MgB2 and annealing‐induced intermetallic phases notably enhances hardness (up to 6) and improves hydrophilicity and antibacterial traits in the coating. [ABSTRACT FROM AUTHOR]

1070 aluminum has good plasticity, but its anisotropy and low dissolution rate limit its application as a soluble sealing ring. To solve the existing plastic anisotropy problem of 1070 aluminum-rolled plate, the effect of heat treatment and copper plating were studied. The results of static uniaxial tensile tests showed that the average elongation of the heat-treated samples increased by 50.54% and the standard deviation of the elongation in different directions decreased by 28.42%. The simulated setting and pressure-stabilizing test further showed that the sealing ring after heat treatment has better sealing performance. Copper plating containing massive uniformly distributed micropores was prepared by electroless plating. The morphology and elements distribution of the copper plating were observed by optical microscope and scanning electron microscope. The dissolution rate and corrosion behavior were characterized by immersion experiment and the electrochemical test. The results showed that the average dissolution rate of copper-plated samples increased by two orders of magnitude compared with 1070 aluminum and a large number of pitting pits with the maximum pitting depth of about 2400 μm generated on the surface of the copper-plated samples due to the synergistic effect of Cl− and "Al-Cu" galvanic corrosion. [ABSTRACT FROM AUTHOR]

An ultrafine-grained Al71Ni14.5Co14.5/CNT poly-quasicrystal (QC/CNT) composite was synthesized using spark plasma sintering of powder components developed through electroless Ni-P/CNT plating of Co particles and mechanical alloying. The performance of the synthesized samples was studied using various testing methods, such as room temperature/hot compression, wear, and corrosion tests. The results were compared to the properties of alloy samples fabricated from raw and coated powders (without CNTs). The wear rate and friction coefficient of the quasicrystalline samples improved significantly due to the contribution of the CNTs. The wear rate of the CNT-containing specimens was 0.992 × 10−4 mm3/N/m, which is 47.1% lower than that of the QC sample. The positive impact of the CNTs on the corrosion potential and current density was further validated by the potentiodynamic polarization tests in a saline solution. However, these improvements in surface properties came at the cost of a 21.5% reduction in compressive strength, although the compressive strength still remained above 1.1 GPa at 600 °C. The results highlight an interesting trade-off between surface properties and mechanical strength, pointing toward the development of materials suitable for extreme conditions. [ABSTRACT FROM AUTHOR]

Hydrogen production from water splitting is considered the most environment-friendly and sustainable method to acquire energy. Alkaline water electrolysis has been widely employed for hydrogen production, but it is still challenging to prepare non-precious metals electrocatalysts to replace the noble-metal-based catalysts. Here we proposed electroless method to prepare a NiCoP nanocrystalline thin flim as efficient electrocatalysts. The morphology and mechanisms of the 45-minute alloy films deposited on Cu substrate were characterized by SEM, XRD, and XPS techniques, moreover, LSV, EIS, and CP were applied to analyze the electrochemical behavior. The nanocrystalline NiCoP45min alloy exhibits higher hydrogen evolution reaction (HER) activity than platinum sheet. An overpotential of -98 mV and a Tafel slope of 47.94 mV·dec−1 at 10 mA·cm−2 was achieved with the catalyst during HER in an alkaline medium. Additionally, its excellent catalytic activity is confirmed by a low Rt value 2.48 Ω. Remarkably, this catalyst also exhibits high HER stability for about 45 h in an alkaline electrolysic solution. [ABSTRACT FROM AUTHOR]

Taking advantage of its high-temperature resistance and elongation properties, conductive-coated polyetheretherketone (PEEK) filament yarn can be used as a textile-based electroconductive functional element, in particular as a strain sensor. This study describes the development of electrical conductivity on an inert PEEK filament surface by the deposition of metallic nickel (Ni) layers via an electroless galvanic plating process. To enhance the adhesion properties of the nickel layer, both PEEK multifilament and monofilament yarn surfaces were metalized by plasma torch pretreatment, followed by nickel plating. Electrical characterizations indicate the potential of nickel-coated PEEK for structural monitoring in textile-reinforced composites. In addition, surface energy measurements before and after plasma torch pretreatment, surface morphology, nickel layer thickness, chemical structure changes, and mechanical properties were analyzed and compared with untreated PEEK. The thickness of the Ni layer was measured and showed an average thickness of 1.25 µm for the multifilament yarn and 3.36 µm for the monofilament yarn. FTIR analysis confirmed the presence of new functional groups on the PEEK surface after plasma torch pretreatment, indicating a successful modification of the surface chemistry. Mechanical testing showed an increase in tensile strength after plasma torch pretreatment but a decrease after nickel plating. In conclusion, this study successfully developed conductive PEEK yarns through plasma torch pretreatment and nickel plating. [ABSTRACT FROM AUTHOR]