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Development of heavy gas oil (HGO) desulphurisation (DS) through altering the composition of employed catalysts is crucial to enhance the quality of clean fuels production. Therefore, this research work reports an effective low-cost desulphurization performance for HGO fraction using unsupported nickel particles, of mixed compositions, having morphologies as nanotube and nanoflower-like as novel catalysts. The introduced structures were synthesised by electroless deposition technique using two reducing agents. The various characteristics of these catalysts were confirmed by XRD, TEM, BET and TGA analysis. The results of gas oil desulfurization revealed that the use of different reducing agents during the preparation stage could have an effect on the level of sulfur removal. Particularly, the produced catalyst by using methylamine, as a reducing agent, could have stronger affinity towards DS process compared to that of the obtained catalyst by hydrazine. Specifically, the catalyst of the superior DS activity could exhibit 97.5% sulfur removal from a heavy gas oil feedstock contains 10,000 ppm as sulfur content. [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 enhanced catalytic properties of bimetallic nanoparticles have been extensively investigated. In this study, bimetallic Ag-M (M = Au, Pt, or Pd) cotton fabrics were fabricated using a combination of electroless deposition and galvanic replacement reactions, and improvement in their peroxidase-mimicking catalytic activity compared to that of the parent Ag fabric was studied. The Ag-Pt bimetallic nanozyme fabric, which showed the highest catalytic activity and ability to simultaneously generate hydroxyl (•OH) and superoxide (O2•−) radicals, was assessed as a urine glucose sensor. This nanozyme fabric sensor could directly detect urinary glucose in the pathophysiologically relevant high millimolar range without requiring sample predilution. The sensor could achieve performance on par with that of the current clinical gold standard assay. These features of the Ag-Pt nanozyme sensor, particularly its ability to avoid interference effects from complex urinary matrices, position it as a viable candidate for point-of-care urinary glucose monitoring. [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]

Featured Application: The technology presented in this work enables the fabrication of conductive patterns on flexible mica substrates through its functionalization with TiO2. This approach allows for the photocatalytic patterning of electroless copper deposition Ag-based catalyst, which facilitates a versatile and scalable route for creating conductive layers on flexible inorganic substrates, making it suitable for applications in electronics and, as demonstrated, sensing device fabrications. The formation of conductive copper patterns on mica holds promise for developing cost-effective flexible electronics and sensing devices, though it is challenging due to the low adhesion of mica's atomically flat surface. Herein, we present a wet-chemical method for copper patterning on flexible mica substrates via electroless copper deposition (Cu-ELD). The process involves pre-functionalizing 50 µm thick muscovite mica with a titanium dioxide (TiO2) layer, via a sol–gel dip-coating method with a titanium acetylacetonate-based sol. Photolithography is employed to selectively activate the TiO2-coated mica substrates for Cu-ELD, utilizing in situ photodeposited silver (Ag) nanoclusters as a catalyst. Copper is subsequently plated using a formaldehyde-based Cu-ELD bath, with the duration of deposition primarily determining the thickness and electrical properties of the copper layer. Conductive Cu layers with thicknesses in the 70–130 nm range were formed within 1–2 min of deposition, exhibiting an inverse relationship between plating time and sheet resistance, which ranged from 600 to 300 mΩ/sq. The electrochemical thickening of these layers to 1 μm further reduced the sheet resistance to 27 mΩ/sq. Finally, the potential of Cu-ELD patterning on TiO2-functionalized mica for creating functional sensing devices was demonstrated by fabricating a functional resistance temperature detector (RTD) on the titania surface. [ABSTRACT FROM AUTHOR]

In recent years, protective coatings have become crucial in graphene‐based chemical studies. This research investigates the anticorrosive properties of coatings created by co‐depositing carbon compounds. Electroless Ni−P‐PAA@F‐GO coatings were applied to stainless steel by adding various amounts of PAA@F‐GO particles to the Ni−P bath. The coated samples were analyzed using X‐ray diffraction and micro‐hardness tests, revealing a peak hardness of 764 HV at 30 mg/L PAA@F‐GO, compared to 521 HV for standard Ni−P coatings. Corrosion performance was evaluated in a 3 % sodium chloride solution, showing that despite a higher corrosion‐erosion rate. Although the coated samples exhibited a corrosion‐erosion rate 4.7 times higher than untreated samples, the mass loss was notably more pronounced in the untreated samples. The study found that adding PAA@F‐GO particles improved corrosion resistance and durability, with optimal results at a specific particle concentration. The enhanced performance is attributed to the increased roughness, impermeability, and hydrophobicity of the functionalized graphene oxide. [ABSTRACT FROM AUTHOR]

In this study, the impact of three different principles of surface activation techniques for polyamide fibers on the formation of conductive percolation during the subsequent electroless copper deposition process was investigated. The techniques used are (1) polyamide complexation using a solution mixture of calcium chloride, ethanol and water, (2) atmospheric plasma surface treatment and (3) grafting of 2‐hydroxyethylmethacrylate by radical induced polymerization. As a result, the percolation threshold was shifted to lower copper contents. The copper content required to form conductive structures was reduced ranged between 59% and 89%, depending on the activation techniques. Furthermore, the deposition time was reduced by 37%–57%, resulting in a faster build‐up of the percolation on the fabric. Changes in wetting behavior and substrate surface topography were identified to be the main reasons for these observations. While all applied surface activation techniques led to higher copper contents compared to unmodified reference, the atmospheric plasma modification led to the highest copper contents during the deposition process and a more uniform appearance of the metallised layer. Highlights: Three different fiber surface activation methods are evaluated.Fiber surface activation increases wetting and polymer‐metal adhesion.Activated polymer surface leads to faster copper deposition and percolation.Atmospheric plasma modification is the most efficient technique. [ABSTRACT FROM AUTHOR]

Endowing artificial muscles with perceptual function, as an octopus does, is highly desired but still suffering from interfacing mismatch between actuating and sensing units in a thin fiber. Herein, an artificial neuromuscular fiber capable of electrically responding to external strain/temperature and actuation path with power supply is reported by using polymer‐assisted metal deposition to firmly coat Cu nanoparticles on the surface of liquid crystal elastomer (LCE). The LCE core acts as an actuator, while the wrinkled Cu sheath provides environment interaction and actuation monitoring. Benefiting from the levodopa/polyethyleneimine interface design, this fiber exhibits large reversible contraction (47.61%), fast strain rate (370% s−1), high output power density (663.75 W kg−1) and reliable durability (1000 cycles) under electrical stimulation. Furthermore, by combining as‐made fiber arrays with electronic system and computing algorithm, this machine learning‐assisted artificial neuromuscular system can actuate the Chinese shadow puppetry and recognize its body movements with high accuracy. This work paves a revolutionary way for fabricating next‐generation flexible robots. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) films are widely used in smart windows, automobile mirrors, and low-power displays due to their capability of reversibly changing color under an external potential. Transition metal oxides, due to their ability to switch between multiple oxidation states, are primarily used as EC films. They require low operating power and provide high coloration efficiency in EC applications. However, their thin-film fabrication through a low-cost and scalable process is still challenging. Here, nickel oxide (NiO) EC films have been synthesized by room-temperature electrochemical oxidation of Ni thin films. The Ni films were grown by electroless deposition and annealed at three different temperatures of 100°C, 200°C, and 300°C. The morphological, optoelectronic, and electrochemical properties of the films have been comparatively analyzed to obtain an optimized EC film. The NiO film annealed at 100°C exhibited superior properties with coloration and bleaching times of 1.8 s and 2.9 s, respectively, and a coloration efficiency of 20 cm2/C. This annealed film is further used to fabricate a EC device with NiO and tungsten oxide (WO3) as the electrode layers and a phosphoric acid-based gel as the electrolyte. The low-temperature deposition process used here can also be extended to flexible substrates. [ABSTRACT FROM AUTHOR]

Fabrication aspects of PdO thin films and coatings are reviewed here. The work provides and organizes the up-to-date information on the methods to obtain the films. In recent years, the interest in Pd oxide for different applications has increased. Since Pd can be converted into PdO, it is instructive to pay attention to the preparation of the pure and the alloyed Pd films, heterostructures, and nanoparticles synthesized on different substrates. The development of PdO films is presented from the early reports on coatings' formation by oxidation of Pd foils and wires to present technologies. Modern synthesis/growth routes are gathered into chemical and physical categories. Chemical methods include hydrothermal, electrochemical, electroless deposition, and coating methods, such as impregnation, precipitation, screen printing, ink jet printing, spin or dip coating, chemical vapor deposition (CVD), and atomic layer deposition (ALD), while the physical ones include sputtering and cathodic arc deposition, laser ablation, ion or electron beam-induced deposition, evaporation, and supersonic cluster beam deposition. Analysis of publications indicates that many as-deposited Pd or Pd-oxide films are granular, with a high variety of morphologies and properties targeting very different applications, and they are grown on different substrates. We note that a comparative assessment of the challenges and quality among different films for a specific application is generally missing and, in some cases, it is difficult to make a distinction between a film and a randomly oriented, powder-like (granular), thin compact material. Textured or epitaxial films of Pd or PdO are rare and, if orientation is observed, in most cases, it is obtained accidentally. Some practical details and challenges of Pd oxidation toward PdO and some specific issues concerning application of films are also presented. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the formation of duplex electroless Ni-P/Ni-B and Ni-P/Ni-B-W alloys through electroless plating process coatings on mild steel using hypophosphite and sodium borohydride as a reducing agent, employing heat-treated. Electroless plating is affordable and suitable for coating convoluted structures. Duplex electroless on mild steel was characterized by X-ray diffraction (XRD), Energy-dispersive X-ray spectrometry (EDS), scanning electron microscopy (SEM) were used to examine the surface and cross-sectional morphologies of the duplex coating, and finally study electrochemical corrosion properties. The analysis reveals that duplex coating yields a thicker, more homogeneous coating with a characteristic cauliflower morphology and spherical nodular structures. The coating was initially amorphous, but finally crystallized when heated to 400 °C. More corrosion resistance was found in the Ni-P/Ni-B and Ni-P/Ni-B-W layers when Ni-B served as the outer covering. This study focuses on the important effects of varying tungsten concentrations and heat treatment on the corrosion resistance, surface quality, and microstructural characteristics of duplex coatings. Showed improved corrosion resistance when exposed to 0.5 g/L of Na2WO4.

3D surface‐enhanced Raman scattering (SERS) platforms with multi‐dimensional hotspots and better tolerance to laser misfocus show great potential for the rapid detection of trace fentanyl. However, the complex fabrication process of 3D fine structures limits the wide‐ranging application of the SERS technique. Herein, a 3D SERS‐active platform is fabricated utilizing a scalable and cost‐effective strategy that involves the electroless deposition of dense Au nanoparticles on natural butterfly wing scales (b‐wings@Au). The resultant b‐wings@Au proves to be sensitive and reliable, with a lower limit of detection of 4× 10−12 m and an enhancement factor (EFexp) of 1.74 × 108 for fentanyl. Furthermore, it exhibits excellent reproducibility, as evidenced by a relative standard deviation of less than 5%, and also demonstrates outstanding stability. The obtained high EFexp is due to the combined effects of the electromagnetic mechanism, involving the enhanced electromagnetic field generated by 3D periodic hotspots, and the chemical mechanism, involving the charge transfer from fentanyl to Au surface. Additionally, the as‐prepared 3D substrate realizes the trace detection of nine fentanyl analogs. This study provides new ideas for the controllable construction of sensitive SERS platforms for drug detection, ultimately advancing the fields of 3D substrates in booming SERS‐based technologies. [ABSTRACT FROM AUTHOR]

Ammonia borane (NH 3 BH 3) as a solid chemical hydrogen storage material with a high hydrogen content can be hydrolyzed under mild conditions to release hydrogen. In this work, Fe–Ni–B/Cu(OH) 2 –Cu foam was synthesized by combining in situ growth and electroless plating. Compared with the binary Fe–B/Cu(OH) 2 –Cu foam and Ni–B/Cu(OH) 2 –Cu foam prepared by the same method, the ternary Fe–Ni–B/Cu(OH) 2 –Cu foam has superior catalytic performance. The Fe–Ni–B/Cu(OH) 2 –Cu foam catalyst was able to achieve a maximum hydrogen production rate of 5.6 ml min−1 cm−2 at 298 K with an activation energy as low as 46.3 kJ mol−1. And more importantly, its catalytic efficiency has hardly decayed after ten cycles. These excellent properties are due to its low activation energy and the large specific surface, multi–site Cu(OH) 2 –Cu–foam carrier. [Display omitted] • Cu(OH) 2 nanowires were grown on the surface of Cu foam by in-situ oxidation. • Ni–Fe–B was supported on the Cu(OH) 2 –Cu foam by electroless deposition. • The HG rate of Fe–Ni–B/Cu(OH) 2 –Cu foam catalyst was 5.6 ml min−1 cm−2 at 298 K. • The activation energy of Fe–Ni–B/Cu(OH) 2 –Cu foam was as low as 46.3 kJ mol−1. • The Fe–Ni–B/Cu(OH) 2 –Cu foam catalyst has excellent cycling stability. [ABSTRACT FROM AUTHOR]

A rapid hydrogen (H 2) sensor operating at room temperature is fabricated using covalent organic framework (COF), namely Pyromellitic dianhydride and tris(4-aminophenyl)amine (PMDA-TAPA), PT COF that has a unique ability to spontaneously reduce Pd2+ into Pd0 nanoparticles without the aid of external reducing agents. The presence of surface redox sites in COF enable the rapid formation of Pd nanoparticles on COF surface under ambient conditions. The generated material, hitherto named as Pd@ amic PT portrayed remarkable H 2 sensing characteristics with a rare combination of high response % (67.3 ± 1) and rapid response/recovery times (5.3/3.5 s, respectively) for 1 % H 2 under ambient conditions. Our results demonstrated appreciable reproducibility, repeatability, and long term stability of sensor that remained unaffected by relative humidity and a high selectivity towards H 2. Further, sensor performance is found to be superior when compared to many Pd loaded 2D material based chemiresistive H 2 gas sensors. [Display omitted] • A room temperature rapid hydrogen sensor was developed using electroless deposition of Pd on a redox active covalent organic framework (Pd@amicPT). • Device fabrication was straightforward and efficient through simple drop casting of colloidal dispersion of Pd@amicPT onto interdigitated electrodes. • Device exhibited rare combination of high response67.3 ± 1% and quick reaction times (5.3/3.5 s) for 1% H 2 under ambient conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] Magnetic particles are widely used in many adsorption and removal processes. Among the many types of magnetic colloids, magnetic Janus particles offer significant possibilities for the effective removal of several components from aqueous solutions. Nevertheless, the synthesis of structures integrating different types of materials requires scalable fabrication processes to overcome the limitations of the available methodologies. Herein, we hypothesized a fabrication process for dual-surface functionalized magnetic Janus particles. The primary silica particles with surface-attached amine groups are further asymmetrically modified by iron oxide nanoparticles, exploiting Pickering emulsion and electroless deposition techniques. The dual surface functionality of the particles is designed for its versatility and demonstrated in two wastewater-related applications. We show that our design can simultaneously remove chromium (VI) and phenol from aqueous solution. The fabricated magnetic-responsive Janus particles are also an effective adsorbent for genomic Deoxyribonucleic acid (DNA) and show superior performance to commercial magnetic beads. Thus, this study provides a novel platform for designing magnetic Janus particles with multifunctional surfaces for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Electroless ZnO (≈900 nm) was deposited on the surface of an Mg-Al alloy (AM60) to reduce its degradation in the marine environment. Uncoated and coated ZnO samples were exposed to an SME simulated marine solution for up to 30 days. The AFM and optical images revealed that the corrosion attack on the ZnO-AM60 surface was reduced due to an increase in the surface hydrophobicity of the ZnO coating (contact angle of ≈91.6°). The change in pH to more alkaline values over time was less pronounced for ZnO-AM60 (by ≈13%), whereas the release of Mg 2 + ions was reduced by 34 times, attributed to the decrease in active sites on the Mg-matrix provided by the electroless ZnO coating. The OCP (free corrosion potential) of ZnO-AM60 shifted towards less negative values of ≈100 mV, indicating that electroless ZnO may serve as a good barrier for AM60 in a marine environment. The calculated polarization resistance ( R p ), based on EIS data, was ≈3 times greater for ZnO-AM60 than that of the uncoated substrate. [ABSTRACT FROM AUTHOR]

Conventional antibiotic treatments for wound infections have the risk of developing microbial resistance, necessitating the search for innovative, alternative solutions like nanoparticles as advanced antibiotics. This work introduces a novel approach for managing acute and chronic wounds by creating an active wound dressing designed to both protect and eliminate bacteria from the injury site. We focused on the electroless deposition of large zinc oxide nanoparticles (ZnO NPs,), aiming for a particle size of around 200 nm to reduce cytotoxicity, onto electrospinned silk fibroin (SF) gauze. We assessed the biocompatibility and antimicrobial effectiveness of the ZnO NP-embedded silk dressing against gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Our analysis indicates that incorporating ZnO nanoparticles into silk wound dressings maintains biocompatibility, achieving 70% cell viability while suppressing the growth of S. aureus and P. aeruginosa, particularly during the initial 24 h after application. By employing 200 nm particle sizes, we facilitated a significant release of zinc ions without producing harmful reactive oxygen species (ROSs) that could damage both bacteria and host tissues. These findings emphasize the therapeutic potential of bioresorbable bandages enhanced with large ZnO nanoparticles, presenting an innovative approach to clinical wound treatment. [ABSTRACT FROM AUTHOR]

Metal matrix nanocomposite coatings are promising for tribological applications given their superior hardness and wear resistance compared to metals. The point of this study was to describe the shape and long‐term performance of nickel‐based coatings that were put on stainless steel using electroless codeposition and made stronger with nanoparticles of zirconia (ZrO2) and alumina (Al2O3). Scanning electron microscopy showed the uniform incorporation of nanoceramics within nickel matrices. Pin‐on‐disk tribotests evaluated wear performance across loads from 5 to 15 N and sliding speeds up to 480 cm/min. Increasing nanoparticle content from 2 to 4 g/L markedly reduced wear rate due to enhanced hardness and density. At all tested loads, Ni‐ZrO2 and Ni‐Al2O3 nanocomposites exhibited considerably lower wear than monolithic nickel. The nanometal matrix particles hindered plastic deformation, with weight losses up to 68% lower than base nickel. Initially, wear resistance rose proportionally with sliding speed resulting from protective oxide layers until abrasive wear prevailed. The nanoparticle reinforcement dramatically extended durability, making it ideal for tribological systems involving mixed or abrasive conditions. More research needs to be done to find the best compositions and other matrix materials to use for these nanoscale strengthening effects. [ABSTRACT FROM AUTHOR]

This study describes using carbon fibers coated with magnetic material as a filler in polyethylene for EMI shielding. It investigates how to utilize barium ferrite (BaFeO3) as a conducting filler in a polyethylene matrix by optimizing the conditions for its electroless deposition onto carbon fibers. Various polymer nanocomposite samples were prepared using varying concentrations of BFO@CF. Scanning electron microscopy is used to assess the surface appearance of the composite and the distribution of BFO@CF within the polymer matrix. Including MWCNT/graphene nanoplatelets exhibit superior shielding properties, and the polymer composite with the BFO@CF demonstrates enhanced mechanical properties. The 8.2 to 12.4 GHz frequency range is used to study the EMI shielding properties. For the composition ratio of LDPE: MWCNT: GNP: BFO@CF (50 : 5 : 47.5 : 2.5), a maximum shielding of 67 dB was attained. After BFO@CF was added to the matrix, the absorption mechanism rather than the reflection mechanism dominated the shielding mechanism. A thorough evaluation and discussion of the shielding mechanism and parameters are presented. [ABSTRACT FROM AUTHOR]

Tailoring a material's surface with hierarchical structures from the micro‐ to the nanoscale is key for fabricating highly sensitive detection platforms. To achieve this, the fabrication method should be simple, inexpensive, and yield materials with a high density of surface features. Here, using benchtop fabrication techniques, gold surfaces with hierarchically structured roughness are generated for sensing applications. Hierarchical gold electrodes are prepared on pre‐stressed polystyrene substrates via electroless deposition and amperometric pulsing. Electrodes fabricated using 1 mm H[AuCl₄] and roughened with 80 pulses revealed the highest electroactive surface area. These electrodes are used for enzyme‐free detection of glucose in the presence of bovine serum albumin and achieved a limit of detection of 0.36 mm, below glucose concentrations in human blood. The surfaces nanoroughened with 100 pulses also showed excellent surface‐enhanced Raman scattering (SERS) response for the detection of rhodamine 6G, with an enhancement factor of ≈2 × 106 compared to detection in solution, and for the detection of a self‐assembled monolayer of thiophenol, with an enhancement factor of ≈30 compared to the response from microstructured gold surfaces. It is envisioned that the simplicity and low fabrication cost of these gold‐roughened structures will expedite the development of electrochemical and SERS sensing devices. [ABSTRACT FROM AUTHOR]

This study introduces a novel dual-metal electroless deposition (ELD) technique to fabricate highly conductive cotton fabrics with superior air stability. Copper (Cu) and nickel (Ni) were deposited onto cotton fabrics with varying weave designs (plain and mesh) to investigate the effects of metal type and fabric structure on conductivity and stability. Each fabrication step included pretreatment process, silanization, polymerization, and ELD, with success validated by water contact angle measurements. Surface morphology and elemental mapping results confirmed uniform metal deposition, while XPS and XRD analyses provided detailed chemical composition and crystallinity information. It was found that while Cu-deposited fabrics exhibited excellent initial conductivity, they suffered from poor air stability. Ni-deposited fabrics demonstrated improved air stability, further influenced by the fabric's weave design (plain and mesh). Notably, this innovative study for dual Ni–Cu deposition strategy significantly enhanced the air stability of copper-coated fabrics while maintaining high conductivity. [ABSTRACT FROM AUTHOR]

[Display omitted] Ni–P coatings, with their high microhardness (HV) and wear resistance, have been proposed as a viable alternative to hard chromium. However, wear testing experiments on electroless Ni–P coatings were conducted under a variety of conditions, including test equipment, load, substrate materials and counterface materials, resulting in unreliable comparative evaluations of experimental results. Therefore, this article presents an analysis of experimental research on Ni–P and Cr coatings, as well as a statistical analysis of the results obtained under similar conditions. The results of simultaneous wear tests on Ni–P and Cr coatings published from 1958 to 2022 were used for evaluation and comparative analysis. The relative wear of Ni–P versus hard Cr was calculated from experimental data and analyzed using statistical methods such as Tukey's statistical methods, nonparametric and parametric statistics. This review found that the wear performance of electroless nickel coatings generally does not match that of hard chromium coatings. The results of this analysis indicate that: (i) Ni–P coating can be used as a protective and hardening coating; (ii) the wear resistance of the electroless Ni–P coating, being 1.9 ± 0.4 times less, does not reach the same level of wear resistance as that of hard Cr; (iii) there is a tendency for the wear resistance of Ni–P to gradually approach the wear resistance of Cr; (iv) the dependence of the wear rate on the phosphorus content of the Ni–P alloy indicates that the minimum possible wear rate is achieved at a P content of about 4–7 wt%. The search for effective alternatives to hard chromium plating is ongoing, and this review has identified several areas where effective engineering solutions could be found. [ABSTRACT FROM AUTHOR]

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This work demonstrates a completely wet-chemical procedure for the fabrication of a functional impedimetric humidity-sensing device on a titania (TiO2) surface. Optically transparent anatase TiO2 thin films were deposited on a glass substrate via dip-coating from a titanium tetraisopropoxide (TTIP)–acetylacetonate (AA)-based sol and surface-functionalized with a nickel oxide (NiOx) layer by ultraviolet (UV) photodeposition. Photodeposition was employed to form the interdigitated electrode pattern on the TiO2 surface as well through activation with a silver catalyst to promote electroless copper deposition. The relative humidity (RH) response of the pristine TiO2- and NiOx/TiO2-functionalized sensors was studied by impedance (Z) measurements in the 15%–90% RH range. It was found that while NiOx functionalization significantly dampens the RH–Z functional dependence, it improves its overall linearity and may successfully be employed for the purposeful design of titania-based sensing devices. [ABSTRACT FROM AUTHOR]

Abstract 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.

In this work the nickel-based coatings were obtained by electroless catalytic deposition on light-hardened resins dedicated for 3D printing by SLA method. The effect of external magnetic field application on the properties of nickel-based coatings was determined. During metallization, the magnetic field was applied to the sample’s surface with different orientations. Due to the magnetic properties of metallic ions, the influence of the magnetic field on coatings properties is expected. The coatings were analyzed by Energy-dispersive X-ray spectroscopy (ED S) the X-Ray diffraction (XRD ) methods, and surface morphology was observed by scanning electron microscopy (SEM). The catalytic properties in a hydrogen evolution reaction (HER ) were measured by electrochemical method in 1 M NaOH solution. The best catalytic activity has been observed in the case of the ternary Ni-Fe-P alloy deposited under a parallel magnetic field. The primary outcome of the presented research is to produce elements based on 3D printing from resins, which can then be metallized and used for highly-active materials deposited on complex 3D models. Furthermore, these elements can be used as low-cost, highly-developed sensors and catalysts for various chemical processes.

High-performance fiber architectures and the incorporation of active nanomaterials are fundamental to advancing fiber-based supercapacitors. Herein, we rationally designed a multifunctional graded structured fibrous electrode with copper phosphosulfide nanosheets (CuS|P NSs) in situ growth on a Cu-coated graphene fiber (CuS|P-CuGFs) for highly energy-dense asymmetric supercapacitors. In particular, applying a Cu-metal coating on the graphene fiber effectively enhanced the electrode conductivity and mechanical durability with a minimum compromise over density. Moreover, the interconnected CuS|P NSs exhibited enhanced redox activity and facilitated ion transport and accumulation. As a result, the CuS|P-CuGF fiber electrodes exhibited high electrical conductivity (697.8 S cm–1), appreciable mechanical strength (285.0 ± 8.4 MPa), and superior electrochemical performance. Significantly, the fiber electrodes demonstrated an outstanding specific capacitance of 1460.9 mF cm–2 at a current density of 3 mA cm–2 in a 3 M KOHaq electrolyte. Moreover, when assembled in an asymmetric supercapacitor, the device exhibited an areal energy density as high as 15.3 μW h cm–2 at a power density of 1.1 mW cm–2 along with excellent bending stability (94.3% retention of the capacitance after 500 cycles of bending at R = 10 mm). The featured work thus provides a facile but robust fiber electrode design method to realize highly energy-dense flexible energy storage devices. [ABSTRACT FROM AUTHOR]

The catalytic electroless plating on insulating substrate holds great potential in additive manufacturing of printing circuits. A tri-layer interpenetration architecture was constructed to improve the peeling strength of Cu plating layer. The corona-treated PET was coated by epoxy resin, which served as ground floor for the rooting of Cu NWs. Benefiting from high aspect ratio, the ends of Cu NWs were exposed to surface. Which assembled into middle layer, forming 3D Cu NWs catalytic arrays. Along with Cu electroless plating, the catalytic arrays were gradually filled up and covered by the top layer of Cu plating. Both epoxy resin layer and Cu plating layer were deeply rooted by Cu NWs, which afforded the Cu plating layer with 5B adhesion, an increase of 86% compared to that of Cu MSs catalyst. Through investigating the subsidence behavior of Cu NWs in epoxy resin adhesive layer, the strengthen mechanism of peeling strength of Cu plating layer has been validated. [ABSTRACT FROM AUTHOR]

This study reports on the use of supercritical CO2 (scCO2) for the metallization of ultrahigh-molecular-weight polyethylene (UHMW-PE) filaments, which are used as functional components in weavable devices. UHMW-PE is well known for its chemical and impact resistance, making it suitable for use in bulletproof clothing and shields. However, its chemical resistance poses a challenge for metallization. By utilizing scCO2 as the solvent in the catalyzation process, a uniform and defect-free layer of Ni-P is successfully deposited on the UHMW-PE filaments. The deposition rate of Ni-P is enhanced at higher temperatures during the scCO2 catalyzation. Importantly, the durability of the Ni-P-metalized UHMW-PE filaments is improved when the scCO2 catalyzation is carried out at 120 °C, as evidenced by minimal changes in electrical resistivity after a rolling test. [ABSTRACT FROM AUTHOR]

The effects of additives on the deposition rate, surface morphology, Ni and P elemental content of the electroless plating layer, and roughness of the electroless plating Ni-P layer were investigated. In an electroless plating Ni-P system, ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) and sodium hypophosphite monohydrate were used as the complexing agent and reductant, respectively. The linear sweep voltammetry (LSV) polarization curve results showed that the compound addition of 1.0 mg L−1 L-tyrosine, 2.0 g L−1 saccharin, and 6.0 mg L−1 sodium dodecyl sulfate (SDS) could inhibit sodium hypophosphite oxidation and nickel ion reduction, which eventually reduced the Ni-P deposition rate. The Tafel polarization curves indicated that the compound additives obviously improved the corrosion resistance of the Ni-P electroless plating layer. Field emission scanning electron microscopy (SEM) images showed that the composite additives generated fine and uniform Ni-P electroless plating particles and enhanced the density, eliminated the surface cracks, and reduced the pinholes on the electroless plating layer surface. Atomic force microscopy (AFM) tests showed that the addition of complex additives improved the smoothness of the plated layer, the Ra value was reduced from 135.0 nm to 53.2 nm, and the Rq value was reduced from 164.0 nm to 93.0 nm. The final composition and implementation conditions of the EDTA-2Na-based Ni-P electroless plating system were determined. The deposition rate was 10.44 μm h−1, the P content of the electroless plating layer was 2.2%, and the electroless plating player was silver-white and bright. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) integration has become a leading approach in chip packaging. The interconnection density and reliability of micro-bumps in chip stacking are often threatened by high bonding temperatures. The method of building chip-to-chip interconnections by electroless deposition of metal has its distinct merit, while the interfacial defect issue, especially that related to voiding during the merging of opposite sides, remains largely unsolved. In this study, to trace the influencing factors in the voiding, the growth characteristics of the electroless all-copper interconnections were examined by carrying out deposition experiments in a microfluidic channel device. The results show that when the gap between the opposite copper bumps to be electrolessly merged is as low as 10 μm, significant voids appear at the inflow side and the top of the copper bumps because the hydrogen cannot be expelled in time. A finite-element flow model of the plating solution between the chips was established, which showed that the flow rate of the plating solution around the copper bumps was much higher than in the merging gap, causing an uneven supply of reactants. Based on these findings, we proposed two potential solutions, one is to improve the flow mode of the plating solution, and the other is to add the reaction inhibitor, 2,2′-bipyridine. Finally, the combination of these two approaches successfully achieved an improved merging quality of the copper joints. [ABSTRACT FROM AUTHOR]

A sustainable nonwoven fabric was developed from natural biodegradable waste poplar seed fibers and PLA fibers using the needle punching technique followed by electroless deposition of copper metal particles. Surface characterization obtained through scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis confirmed the successful integration of copper particles with the poplar-PLA nonwoven. The presence of copper particles significantly improved the mechanical properties of the substrate and endowed it with superior electrical conductivity (∼ 0.6 Ω/cm). The Cu/poplar-PLA fabric exhibited great potential for efficient wearable sensing applications, such as detecting EMG signals induced by the contraction–relaxation of hand muscles and capturing variant pressures (e.g., finger tapping and counterweight pressing) in real-time. In addition, fast heat generation (temperature reached 78.9 °C at 3.5 V within 45 s) with a uniform distribution ensured the viability of the substrate for wearable thermal heating devices. This was further confirmed by heating the Cu/poplar-PLA substrate attached to a hand finger, which resulted in a consistent temperature profile in the selective area of the finger, suggesting its suitability for region-specific temperature management for personalized comfort or therapy. This work offers a novel and facile way to develop sustainable electronic textiles for the next-generation wearable sensing and heating. [ABSTRACT FROM AUTHOR]

Pipe union steel development in the automobile industry necessitates a diversified strategy, notably in terms of surface protection, durability enhancement, and corrosion resistance. This comprehensive research dives into the domain of chemical deposition technologies, primarily electroplating and its derivatives to strengthen steel surfaces against environmental, thermal, and cyclic stressors inherent in car exhaust systems. Electroplating is a flexible technology with numerous applications ranging from corrosion protection and microstructure formation to alloying and the development of high-magnetic force actuators. The research examines electroplating mechanisms, classifies chemical deposition methods, and defines the parameters of an ideal electroplating process. It assesses thin film electrodeposition and autocatalytic or electroless metal deposition, analyzing their benefits, disadvantages, and real-world applications in the automotive industry. It also investigates current research on electroplating applications, environmental problems, and pipe union steel challenges in engineering applications, such as fracture inclinations and material fatigue. Furthermore, this study investigates studies that address environmental contamination caused by electroplating applications, as well as novel methods for reducing hazardous waste. Several experimental and computational researches on steel compositions, alloys, and alternative coatings provide vital insights into enhancing the durability and corrosion resistance of pipe union steel for automotive applications. [ABSTRACT FROM AUTHOR]

Copper metal catalyst seeds have recently triggered much research interest for the development of low-cost and high-performance metallic catalysts with industrial applications. Herein, we present metallic Cu catalyst seeds deposited by an atomic layer deposition method on polymer substrates. The atomic layer deposited Cu (ALD-Cu) can ideally substitute noble metals Ag, Au, and Pd to catalyze Cu electroless deposition. The optimized deposition temperature and growth cycles of an ALD-Cu catalyzed seed layer have been obtained to achieve a flexible printed circuit (FPC) with a high performance electroless plating deposited Cu (ELD-Cu) film. The ELD-Cu films on the ALD-Cu catalyst seeds grown display a uniform and dense deposition with a low resistivity of 1.74 μΩ·cm, even in the through via and trench of substates. Furthermore, the ALD-Cu-catalyzed ELD-Cu circuits and LED devices fabricated on treated PI also demonstrate excellent conductive and mechanical features. The remarkable conductive and mechanical characteristics of the ALD-Cu seed catalyzed ELD-Cu process demonstrate its tremendous potential in high-density integrated FPC applications. [ABSTRACT FROM AUTHOR]

Results are presented from investigating the ferromagnetic resonance spectra of arrays of Co‒Ni and Co‒Fe‒Ni wires with different composition gradients, deposited into polycarbonate track-etched membranes. The effect interfaces and concentration gradients have on the effective fields of the investigated wires is examined. An anomalous angular dependence of the fields of ferromagnetic resonance is observed for the wire arrays at a pore density of ~18% in the membrane. [ABSTRACT FROM AUTHOR]

This study explores MgB2 as a reinforcing agent in electroless deposition on AZ91 magnesium alloy substrates, evaluating its impact on coating properties. X-ray diffraction (XRD) analysis shows that the amorphous Ni-B coating masks initial magnesium peaks, while MgB2 enhances MgB2O(OH)6, MgB2O5, MgO, and MgB2xOy oxide phases. SEM images illustrate morphological shifts from cauliflower-like Ni-B structures to dendritic and fibrous MgB2 forms, with higher MgB2 concentrations leading to granular structures with randomly oriented crystallites resembling platelets, indicating increased magnesium content. MgB2-reinforced Ni-B coatings exhibited higher hardness than the substrate but lower than as-deposited Ni-B. Friction coefficients initially decreased with Ni-B, increased significantly with 0.1 g MgB2, and decreased with higher reinforcements, remaining higher than substrate and as-deposited Ni-B. MgB2 reinforcement increased surface roughness, causing local agglomerations in 0.5 g MgB2 coatings. Contact angle measurements demonstrated enhanced hydrophilicity due to MgB2's superhydrophilic properties influenced by surface roughness. Antibacterial tests revealed superior properties with 0.1 g MgB2, suggesting a transition to MgB2-enriched structures and influencing material properties. While Ni-B/MgB2 coatings improved over substrate, further research is needed to optimize parameters and understand stabilizer effects. These coatings also exhibited superhydrophilicity and promising antibacterial properties, suggesting potential in advanced surface engineering applications.

The formation of conductive copper patterns on mica holds promise for developing cost-effective flexible electronics and sensing devices, though it is challenging due to the low adhesion of mica’s atomically flat surface. Herein, we present a wet-chemical method for copper patterning on flexible mica substrates via electroless copper deposition (Cu-ELD). The process involves pre-functionalizing 50 µm thick muscovite mica with a titanium dioxide (TiO2) layer, via a sol–gel dip-coating method with a titanium acetylacetonate-based sol. Photolithography is employed to selectively activate the TiO2-coated mica substrates for Cu-ELD, utilizing in situ photodeposited silver (Ag) nanoclusters as a catalyst. Copper is subsequently plated using a formaldehyde-based Cu-ELD bath, with the duration of deposition primarily determining the thickness and electrical properties of the copper layer. Conductive Cu layers with thicknesses in the 70–130 nm range were formed within 1–2 min of deposition, exhibiting an inverse relationship between plating time and sheet resistance, which ranged from 600 to 300 mΩ/sq. The electrochemical thickening of these layers to 1 μm further reduced the sheet resistance to 27 mΩ/sq. Finally, the potential of Cu-ELD patterning on TiO2-functionalized mica for creating functional sensing devices was demonstrated by fabricating a functional resistance temperature detector (RTD) on the titania surface.

The design of advanced noble-metal-free electrocatalysts with high activity and good stability for the hydrogen evolution process (HER) is both appealing and challenging. Herein, cauliflower-like Co–B–P nanoparticles anchored on multi-layered g-C 3 N 4 nanosheets (Co–B–P/g-C 3 N 4) are fabricated by a facile electroless deposition method at room temperature. The effect of P/B ratios on electrocatalytic performance of ternary Co–B–P/g-C 3 N 4 catalysts for HER is fully investigated in 1.0 M KOH solution. Due to both the synergetic effect among P, B and Co, and the support of multi-layered g-C 3 N 4 nanosheets, ternary Co–B–P/g-C 3 N 4 catalyst exhibits satisfactory electrocatalytic HER performances. The onset overpotential for the best ternary Co–B–P/g-C 3 N 4 catalyst is only 93 mV, whereas it is 173 mV for binary Co–B/g-C 3 N 4 catalyst. When current density achieves 10 mA cm−2 and 40 mA cm−2, the required overpotentials for ternary Co–B–P/g-C 3 N 4 catalyst are 174 mV and 226 mV, respectively, which are much lower than those of binary Co–B/g-C 3 N 4 catalyst (261 mV and 327 mV). Furthermore, the stability test indicates that ternary Co–B–P/g-C 3 N 4 catalyst possesses a favorable long-term electrochemical stability under alkaline condition. The satisfactory electrocatalytic performances of as-prepared ternary Co–B–P/g-C 3 N 4 catalyst suggest that it is a promising candidate to substitute noble-metal based catalysts for HER. [Display omitted] • The formation of cauliflower-like morphology of CBPG was promoted by the addition of P. • Synergistic effect among Co, B and P promoted electrocatalytic activity of CBPG. • CBPG delivered overpotentials of only 174 mV at current density of 10 mA cm−2. • CBPG maintained good electrocatalytic stability even after 24 h test. [ABSTRACT FROM AUTHOR]

The properties of thin surface layers of polymer substrates should be investigated and controlled for their application in electroless deposition. In this paper, polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) substrates were modified by plasma treatment, ultraviolet (UV)/ozone treatment, or UV (254 nm) irradiation. The chemical and physical properties of the modified layer were studied by measuring contact angle and zeta potential, field-emission scanning electron microscope (FE-SEM) imaging, and infrared spectroscopy. The condition of the surface modification affected oxygenation of the polymer chains. The oxygenation formed hydrophilic surface functional groups and relatively polar low-molecular-weight fragments resulting from the scission of the polymer chains. The surface functional groups and the fragments governed the properties of the modified layer. Adhesive metal films were electrolessly deposited on the thinner modified layer having the hydrophilic functional groups. In contrast, the thicker modified layer containing the fragments decreased the adhesion of the metal films. For example, UV/ozone treatment of the PEN substrate formed the thicker modified layer, on which no adhesive metal films were deposited. These findings illustrate that optimizing the condition of the surface modification thoroughly is feasible to form the modified layer having the chemical and physical properties appropriate for depositing adhesive metal films. [ABSTRACT FROM AUTHOR]

Al-induced electroless bi-layered Co/Sn coating was fabricated on a mild steel substrate by plating the Co layer as a primer and the Sn as an outer layer. This Co/Sn bi-layer coating was prepared by using a dual bath (chloride-based electroless Co and Sn bath) with varying single-layer thickness. The growth rate of the primer and outer layers was evaluated in a temperature range of 60° to 90°C. The morphology, composition, and phase structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffractometer (XRD), respectively. The bi-layer coating showed a significant improvement in corrosion resistance in terms of a reduction in corrosion current and corrosion rate and an increase in polarization resistance compared to the single-layer coating. [ABSTRACT FROM AUTHOR]

Modulating electronic structure of metal nanoparticles via metal–support interaction has attracted intense interest in the field of catalytic science. However, the roles of supporting substrates in regulating catalytic properties of nanozymes remain elusive. In this study, we find that the use of graphdiyne oxide (GDYO) as the substrate for self-terminating growth of Ru nanoparticles (Ru@GDYO) endows the peroxidase-like activity of Ru nanoparticles with intrinsic physiological pH preference and natural horseradish peroxidase (HRP) comparable performance. Ru nanoparticles electrolessly deposited onto GDYO possess a partially oxidized electronic structure owing to limited charge transfer between Ru and GDYO, contributing to the intrinsic physiological pH preference of the peroxidase-mimicking nanozyme. More importantly, the substrate GDYO plays an influential factor in enhancing catalytic activity, that is, the activity of Ru@GDYO is much higher than that of Ru nanoparticles deposited on other carbon substrates including graphene oxides and graphdiyne. To demonstrate the application of Ru@GDYO nanozyme in neutral solutions, we employ Ru@GDYO with nicotinamide adenine dinucleotide (NAD+)-dependent dehydrogenases in physiological conditions to realize a sustainable cascade reaction by means of forming continuous NAD+/dihydronicotiamide adenine dinucleotide (NADH) recycling. Our finding represents a promising perspective on designing high-performance peroxidase-mimicking nanozymes with broader applicability, raising fundamental understanding of structure–activity relationship, and investigating new applications of nanozymes in biological systems. [ABSTRACT FROM AUTHOR]

The present research reports an experimental study of Ni-W-P-nanoTiO2 composite coatings deposited on API X60 low-carbon steel by the electroless method. Electroless bath parameters are optimized to attain maximum deposition rate using the Taguchi design (L9 orthogonal array). Analysis of variance was performed to find out the significance of individual parameters. A confirmation test was performed at the initial and optimal parameter combination obtained from the Taguchi analysis. In addition, the applicability of artificial neural network (ANN) was also examined for the prediction of deposition rate. An ANN 4-7-1 network accurately predicted the deposition rate with a correlation coefficient (R2) valued at 0.9820. Atomic force microscopy and field emission scanning electron microscopy were used to characterize the surface morphology, and energy-dispersive spectroscopy, and X-ray diffraction were used for compositional and phase study of the coatings. The corrosion behavior of nanocomposite coatings was tested in 3.5 wt% NaCl solution by potentiodynamic polarization. The optimum combination was achieved with 24 g/L of reducing agent content, 10 g/L of TiO2 nanoparticles content, bath pH of 9, and a temperature of 80 °C. [ABSTRACT FROM AUTHOR]

Surface-modified nanoplate-shaped thermoelectric materials can achieve good thermoelectric performance. Herein, single-crystalline Bi2Te3 nanoplates with regular hexagonal shapes were prepared via solvothermal techniques. Surface modification was performed to deposit different metals onto the nanoplates using electroless deposition. Nanoparticle-shaped tin (Sn) and layer-shaped palladium (Pd) formed on the Bi2Te3 nanoplates via electroless deposition. For the sequential deposition of Sn and Pd, the surface morphology was mostly the same as that of the Sn-Bi2Te3 nanoplates. To assess the thermoelectric properties of the nanoplates as closely as possible, they were compressed into thin bulk shapes at 300 K. The Sn-Bi2Te3 and Sn/Pd-Bi2Te3 nanoplates exhibited the lowest lattice thermal conductivity of 1.1 W/(m·K), indicating that nanoparticle-shaped Sn facilitated the scattering of phonons. By contrast, the Pd-Bi2Te3 nanoplates exhibited the highest electrical conductivity. Thus, the highest power factor (15 μW/(m∙K2)) and dimensionless ZT (32 × 10−3) were obtained for the Pd-Bi2Te3 nanoplates. These thermoelectric properties were not as high as those of the sintered Bi2Te3 samples; however, this study revealed the effect of different metal depositions on Bi2Te3 nanoplates for improving thermoelectric performance. These findings offer venues for improving thermoelectric performance by sintering nanoplates deposited with appropriate metals. [ABSTRACT FROM AUTHOR]

A novel, biodegradable substrate based, and cost-effective flexible electrochemical sensor was developed for the highly selective and sensitive detection of one of the major neurotransmitters, dopamine, which can be utilised as a disposable electrode for point-of-care diagnostic applications. The active material CuSnB decorated over cellulose paper exhibits good sensitivities of 3.92 μA μM−1 cm−2 with a limit of detection of 0.5 nM. Moreover, the flexible sensor demonstrated superior selectivity towards co-existing metabolites such as ascorbic acid, glucose, and uric acid, in addition to stability at various mechanical deformations. [ABSTRACT FROM AUTHOR]