Nickel Microparticles Research Articles

Enhancing piezoresistive sensitivity of PEDOT:PSS-based strain sensors through nickel microparticles incorporation

Enhancing piezoresistive sensitivity of PEDOT:PSS-based strain sensors through nickel microparticles incorporation

Synthesis of nanoflakes-covered microparticles of nickel-Application for electrocatalytic oxidation and quantitation of nitrofurazone

Nickel microparticles covered with nanoflakes (NMCN) were hydrothermally synthesized in an alkaline solution of acrylamide dissolved in ethylene glycol/ethylenediamine at 200 °C. Structure and morphology of NMCN were characterized by field-emission scanning electron microscopy and X-ray powder diffraction, respectively. NMCN was applied, as an electrode modifier, with a surface concentration of 5.1 × 10−8 mol cm−2, and a detailed study was performed for the kinetics of charge transfer across the modified electrode/electrolyte interface using cyclic voltammetry. For the redox transition of NMCN in an alkaline solution, electron transfer coefficient and apparent charge-transfer rate constant were acquired as 0.65 and 0.6 s−1, respectively. The modified electrode was then applied for a study on the electrocatalytic oxidation of nitrofurazone (NF) on the NMCN surface through an electrochemical-catalytic (EC') mechanism. The oxidation process was followed by a NF diffusion coefficient of 2.9 × 10−6 cm2 s−1 and a catalytic rate constant of 3.0 × 104 cm3 mol−1 s−1. Also, an electron transfer coefficient of 0.40 was attained. The modified electrode was employed as a novel, time-saving, sensitive and simple amperometric sensor for NF, and quantified the drug with a linear range of 30–570 μmol L−1 and a sensitivity of 0.694 ± 0.002 A L mol−1 cm−2. Also, a detection limit of 4.3 μmol L−1 was attained. The sensor was employed for direct assay of NF in the human serum and ointments.

Recovering Nickel‐Based Materials from Spent NiMH Batteries for Electrochemical Applications

AbstractIn this work, we explored the recovering possibilities of nickel‐based products from the cathode materials of spent nickel‐metal hydride (NiMH) batteries collected from car repair centers in Mongolia. Specifically, nickel‐based by‐products such as metallic nickel, Ni microparticles, nickel oxide, nickel chloride, and betta‐phase (β) nickel hydroxide powders are successfully produced. X‐ray diffraction patterns suggested that all samples show high crystallinity and phase purity. Ni microparticles were recovered using a chemical reduction method from a leachate solution prepared by dissolving the cathode of the spent NiMH battery in hydrochloric acid. Notably, β‐Ni(OH)₂ displayed two redox peaks in KOH electrolyte solution, suggesting that it has excellent electrochemical potential and can be reused for the fabrication of new NiMH batteries. To validate the electrochemical performances, we examined the catalytic activity of nickel microparticles as a catalyst for the degradation of Congo red (CR) dye and oxygen evolution reaction (OER). The reduction reaction rate of CR dye in the presence of a nickel catalyst was 2.17×10−3 s−1, significantly higher than the control experiment without a nickel catalyst. These results provide possible solutions for developing sustainable battery systems by recovering different nickel‐based products from spent NiMH batteries.

Multimodal sensing algorithm using thermoelectric dynamics for self-powered skin-like sensory devices

In the rapidly evolving field of electronic skins (e-skins), the development of self-powered sensors has emerged as a promising solution to providing continuous and reliable power sources for embedded sensors. This study introduces a novel approach that incorporates spike-shaped nickel (Ni) microparticles into a styrene-ethylene-butylene-styrene (SEBS) matrix, resulting in a thermoelectric material that functions as both an energy harvester and a pressure sensor, and a multimodal sensing algorithm designed to mitigate pressure sensing errors arising from temperature fluctuations in the thermoelectric self-powered pressure sensor. The Ni-SEBS composite, with a sensing mechanism that identifies changes in the Ni particle percolation state induced by compressive strain, exhibited a high sensitivity of 0.6234 kPa−1. Based on this composite, a dual-channel self-powered sensor was fabricated using the proposed algorithm and attached to the skin; the sensor successfully detected various forms of external pressure applied to the skin without errors due to temperature changes.

Conducting and Magnetic Hybrid Polypyrrole/Nickel Composites and Their Application in Magnetorheology.

Hybrid organic/inorganic conducting and magnetic composites of core-shell type have been prepared by in-situ coating of nickel microparticles with polypyrrole. Three series of syntheses have been made. In the first, pyrrole was oxidised with ammonium peroxydisulfate in water in the presence of various amounts of nickel and the composites contained up to 83 wt% of this metal. The second series used 0.1 M sulfuric acid as a reaction medium. Finally, the composites with polypyrrole nanotubes were prepared in water in the presence of structure-guiding methyl orange dye. The nanotubes have always been accompanied by the globular morphology. FTIR and Raman spectroscopies confirmed the formation of polypyrrole. The resistivity of composite powders of the order of tens to hundreds Ω cm was monitored as a function of pressure up to 10 MPa. The resistivity of composites slightly increased with increasing content of nickel. This apparent paradox is explained by the coating of nickel particles with polypyrrole, which prevents their contact and subsequent generation of metallic conducting pathways. Electrical properties were practically independent of the way of composite preparation or nickel content and were controlled by the polypyrrole phase. On the contrary, magnetic properties were determined exclusively by nickel content. The composites were used as a solid phase to prepare a magnetorheological fluid. The test showed better performance when compared with a different nickel system reported earlier.

Study on wear, corrosion and fatigue properties of dual metallic bearings coated with nickel and aluminum particles

One of the solutions for improving the mechanical properties is coating them with particles, which is carried out by various methods. In this study, dual metallic copper/steel bearings were investigated so that, one of them was an uncoated (S0) and three coated samples, nickel micro-particles (S1), nickel/aluminum micro-particles (S2), and nickel/aluminum nano-particles (S3) were produced. The samples were subjected to mechanical tests including micro hardness, wear, and scratch, and then their corrosion rate and fatigue life were evaluated. The results showed that creating a nano-sized coating on the sample improved their properties compared to the micro-sized and uncoated samples. The highest micro hardness was obtained for sample S3, which was equal to 103.6 HV, 18% higher than sample S0. The lowest wear and corrosion rates were also obtained for sample S3, which were equal to 0.38 mg m−1 and 3.14 mm year−1, respectively. Also, sample S3 had lowest delamination amount in the scratch test equal to 0.17 mm and most number of cycles until failure, 242 thousand cycles, in the fatigue test which was 76% more than the number of cycles spent on sample S0. Additionally, the microstructure of the corroded and worn surfaces of samples were examined by SEM imaging.

Cover Feature: Catalytic Deactivation and Regeneration of Nickel Microparticles in a Home‐Built Microchannel‐Coupled Millireactor: Substrate Specificity and Multiphase Flow Dependency (ChemPhysChem 14/2023)

Cover Feature: Catalytic Deactivation and Regeneration of Nickel Microparticles in a Home‐Built Microchannel‐Coupled Millireactor: Substrate Specificity and Multiphase Flow Dependency (ChemPhysChem 14/2023)

Catalytic Deactivation and Regeneration of Nickel Microparticle in a Home-build Microchannel-coupled-Millireactor: Substrate-Specificity and Multiphase Flow Dependency.

Substrate-assisted product desorption often proposed in heterogeneous catalysis (nanozymes) denounces the catalytic deactivation of heterogenous catalysts. On contrary, the catalytic deactivation of rigid heterogeneous catalysts becomes noticeable in a continuous flow reactor. Surprisingly, it has been addressed inadequately and in an isolated manner. In this study, we have developed a cost-effective non-lithographic method for fabrication of PDMS-based microchannel-coupled-millireactor. Immobilized Nickel particles are resistant to leaching in flow process. During continuous operation, millireactors show strong catalytic activity for reduction of resazurin andp-nitrophenol with a conversion rate of almost 100%. The catalytic poisoning is ubiquitous and being gradually prominent whereas complete catalytic deactivation of magnetic Ni-microparticle is found to be an instantaneous process. Relatively larger-sized resorufin binds predominantly to the surface and thereby blocks the access of substrate to Ni-particle. The dissociations of product molecules - resorufin and p-aminophenol are the rate-limiting steps that caused the abrupt deactivation of Ni-microparticle. The kinetic mechanism of heterogeneous derived from the Langmuir-Hinshelwood mechanism satisfactorily explain the catalytic poisoning and deactivation of Nickel microparticle. This study sheds light on the intricacies of catalytic activity and poisoning of magnetic Nickel microparticles.

Allergenicity and Bioavailability of Nickel Nanoparticles Compared to Nickel Microparticles in Mice

Metal allergy is a common disease that afflicts many people. Nevertheless, the mechanism underlying metal allergy development has not been completely elucidated. Metal nanoparticles might be involved in the development of a metal allergy, but the associated details are unknown. In this study, we evaluated the pharmacokinetics and allergenicity of nickel nanoparticles (Ni-NPs) compared with those of nickel microparticles (Ni-MPs) and nickel ions. After characterizing each particle, the particles were suspended in phosphate-buffered saline and sonicated to prepare a dispersion. We assumed the presence of nickel ions for each particle dispersion and positive control and orally administered nickel chloride to BALB/c mice repeatedly for 28 days. Results showed that compared with those in the Ni-MP administration group (MP group), the Ni-NP administration group (NP group) showed intestinal epithelial tissue damage, elevated serum interleukin (IL)-17 and IL-1β levels, and higher nickel accumulation in the liver and kidney. Additionally, transmission electron microscopy confirmed the accumulation of Ni-NPs in the livers of both the NP and nickel ion administration groups. Furthermore, we intraperitoneally administered a mixed solution of each particle dispersion and lipopolysaccharide to mice and then intradermally administered nickel chloride solution to the auricle after 7 days. Swelling of the auricle was observed in both the NP and MP groups, and an allergic reaction to nickel was induced. Particularly in the NP group, significant lymphocytic infiltration into the auricular tissue was observed, and serum IL-6 and IL-17 levels were increased. The results of this study showed that in mice, Ni-NP accumulation in each tissue was increased after oral administration and toxicity was enhanced, as compared to those with Ni-MPs. Orally administered nickel ions transformed into nanoparticles with a crystalline structure and accumulated in tissues. Furthermore, Ni-NPs and Ni-MPs induced sensitization and nickel allergy reactions in the same manner as that with nickel ions, but Ni-NPs induced stronger sensitization. Additionally, the involvement of Th17 cells was suspected in Ni-NP-induced toxicity and allergic reactions. In conclusion, oral exposure to Ni-NPs results in more serious biotoxicity and accumulation in tissues than Ni-MPs, suggesting that the probability of developing an allergy might increase.

Self-Activating Metal-Polymer Composites for the Selective Electroless Metallization of 3D Printed Parts

Nowadays, polymer based additive manufacturing (AM) is widely recognized as a powerful technology for the fabrication of complex three-dimensional objects of virtually any shape in a time, material, and cost effective way. Thanks to their characteristic advantages over conventional manufacturing strategies, AM technologies are the subject of relevant research efforts. In particular, great attention is placed on developing novel 3D printable materials characterized by improved properties and, among all, by novel functionalities, such as magnetic [1] and conductive properties [2]. In order to do this, the most common strategy relies on doping polymeric matrices with nanoparticles, obtaining thus functional 3D printable polymeric composites.Metal containing composites, in particular, can be exploited for their magnetic properties or for their mechanical behavior but also for their potential capability to trigger electroless deposition. It is well-known that electroless plating requires the presence of a catalytic surface, which can be constituted by the metallic particles embedded in the 3D printed composite. In this way, the need to activate the surface of non-conductive polymeric 3D printed parts can be avoided [3]. In addition, metallization can be carried out selectively by fabricating parts in a multi-material printing process [4] with both metal loaded and non-loaded materials. Since only the layers that contain the particles can metallize, conductive regions can be alternated with insulating zones to create metallic functional patterns on the surface of printed parts. This approach can enable the 3D printing of selectively self-metallizing parts, with possible applicability in the production of flexible and highly tridimensional electronic circuits, radiofrequency devices, microelectromechanical systems or microfluidic setups.The present work focuses on the development of a stereolithography (SLA) printable composite based on an acrylate resin loaded with nickel microparticles and its application as self-catalytic material for electroless metallization. This approach, unprecedented for SLA resins, eliminates the need of noble metal activation of the surface. Moreover, the usage of Ni is of great interest also due to the other properties that it can potentially impart to the printed parts: improved mechanical properties, high thermal conductivity, magnetizability. The SLA printability of the metal-loaded resin is assessed and the morphological properties of the 3D printed composites are investigated. Subsequently, the functional properties of the composites are determined, placing a particular emphasis on their capability to trigger NiP and Cu electroless deposition. Finally, the possibility to selectively metallize only specific areas is successfully demonstrated by metallizing a Ni-loaded pattern printed on a Ni-free base.[1] Huber et al.; Appl. Phys. Lett. 109, 162401 (2016)[2] Postiglione et al.; Compos. Part A Appl. Sci. Manuf. 76, 110-114 (2015)[3] Bernasconi et al.; J. Electrochem. Soc. 164, B3059–B3066 (2017)[4] Choi et al.; J. Mater. Process. Technol. 211, 318–328 (2011)

Conducting and magnetic hybrid polyaniline/nickel composites

Hybrid organic/inorganic polyaniline/nickel composites were prepared by the in-situ oxidation of aniline hydrochloride with ammonium peroxydisulfate in the presence of various portions of nickel microparticles. Electron microscopies demonstrated the coating of nickel with polyaniline. FTIR and Raman spectroscopies indicated the reduced degree of polyaniline protonation. As a consequence, the composites containing 7.2–58.8 wt% of nickel had the conductivity of the order of 10−3–10−2 S cm−1, i.e. several order of magnitude lower than the conductivity of polyaniline or nickel. The conductivity as a function of applied pressure is also reported. Relatively low conductivity of composites is explained by the partial reduction of polyaniline with hydrogen gas evolved during the synthesis and consequent hydrogenation of polyaniline catalysed by nickel. The accompanying partial dissolution of nickel manifests itself by the reduced composite yield. The reason why hydrogen is generated mainly after the synthesis of polyaniline is discussed. The magnetic properties afforded by nickel are also reported. The composites dispersed in thermoplastic polyurethane matrix providing mechanical properties have been tested for electromagnetic interference shielding.

Study of New Nitrogen-Fireable Copper-Nickel Thick Film Paste Formulation Compatible with Thick Printed Copper.

This paper is focused on a new copper-nickel thick film resistive paste which was designed and experimentally developed for the realization of low-ohmic power resistors. This copper-nickel paste has been designed for use in combination with thick printed copper conductors and in comparison with conventional ruthenium-based thick film resistor pastes allows firing in a nitrogen protective atmosphere. The copper-nickel paste was prepared from copper and nickel microparticles, glass binder particles and a combination of organic solvents optimized for its firing in a nitrogen atmosphere. This paper covers a detailed description of copper-nickel paste composition and its thermal properties verified by simultaneous thermal analysis, a description of the morphology of dried and fired copper-nickel films, as well as the electrical parameters of the final printed resistors. It has been proven by electron microscopy with element distribution analysis that copper and nickel microparticles diffused together during firing and created homogenous copper-nickel alloy film. This film shows a low temperature coefficient of resistance ±45 × 0−6 K−1 and low sheet resistance value 45 mΩ/square. It was verified that formulated copper-nickel paste is nitrogen-fireable and well-compatible with thick printed copper pastes. This combination allows the realization of power substrates with directly integrated low-ohmic resistors.

Dual-reductant synthesis of nickel nanoparticles for use in screen-printing conductive paste

This study presents a systematic study in which sodium borohydride and hydrazine were used successively as reducing agents for the synthesis of nickel nanoparticles in an aqueous medium. The size of nickel nanoparticles could be controlled ranging from 11 to 48 nm by adjusting the concentration of hydrazine and the reaction temperature. A product yield of synthesized nanoparticles could achieve as high as 86.5%. As alternatives to silver pastes in some applications, nickel pastes have attracted growing interest because of the lower cost. By the use of nickel nanoparticles as fillers of the conductive pastes, low temperature sintering can be achieved. To avoid film cracking and to improve conductivity, bimodal screen-printing pastes containing different weight ratios of nickel microparticles and nanoparticles were prepared. A micro-to-nanoparticle weight ratio of 2 was found to be the optimal ratio for the nickel paste formulation, resulting in a volume resistivity of 122 μΩ∙cm for a printed film after sintering at a targeted temperature of 600 °C.

Phase-Vortex Removal for Quantitative X-Ray Nanotomography with Near-Field Ptychography

X-ray ptychotomography in the near-field regime is a promising technique for high-resolution, quantitative, and nondestructive investigations in materials science, paleontology, and biomedicine. X-ray near-field ptychography has been previously demonstrated in projection and tomography mode, but the quantitativeness of the reconstructed data has never been discussed in detail. Here, we use measurements of a sample made of aluminum and nickel microparticles to evaluate the quantitativeness of the volumetric mass-density data. Moreover, we propose an algorithm (VortRem) for the removal of phase vortexes, a type of artifact that frequently occurs in holographic methods. VortRem and the results presented here may be fundamental for extending the applicability of this emerging technique to quantitative three-dimensional characterization studies of light as well as dense samples down to the nanoscale.

Multivariate analysis of the 3D composites based on nickel microparticles

This paper presents multivariate analyses of the experimental parameters obtained in the scientific experiments on eight sample fabrics of 100% cotton with electrically conductive properties and electromagnetic achieved through traditional treatments such as padding with antistatic agents, and direct printing or scraping with a polymeric paste based on nickel (Ni). Textile printing was obtained using polymers such as polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyacrylate, ammonium salt, carboxylic acid Copolymer polyester, and Ni microparticles. For the eight samples that have been analyzed, the morphology of the surfaces using SEM (scanning electron microscope) with magnification 2000–8000x and electronic magnification microscopy with 4x, assessed the resistance to wet rubbing and dry the resistance of the surface after treatment in the solution of alkaline and acid sweat. Also, the samples above referred have been analyzed by spectrophotometry to evaluate the transmittance, and reflectance of the electromagnetic waves. It can specify that after treatments in acid or alkaline sweat solutions, the resistance of the surface has decreased by 103–105. It has been observed that for samples treated with acid or alkaline sweat, the reflectance was increased in comparison with the reflectance obtained for the original samples. The multivariate analysis provided refers to the study of some physic-chemical and optical parameters, of the samples collected, such as thickness, pH, reflectance, and transmittance

Production of 3D-printed disposable electrochemical sensors for glucose detection using a conductive filament modified with nickel microparticles

Three-dimensional printing techniques have been widely used in the fabrication of new materials applied to energy, sensing and electronics due to unique advantages, such as fast prototyping, reduced waste generation, and multiple fabrication designs. In this paper, the production of a conductive 3D-printing filament composed of Ni(OH)2 microparticles and graphene within a polylactic acid matrix (Ni-G-PLA) is reported. The nanocomposite was characterized by thermogravimetric, energy-dispersive X-ray spectroscopic, scanning electronic microscopic, Raman spectroscopic and electrochemical techniques. Characteristics such as printability (using fused deposition modelling), electrical conductivity and mechanical stability of the polymer nanocomposite were evaluated before and after 3D printing. The novel 3D-printed disposable electrode was applied for selective detection of glucose (enzyme-less sensor) with a detection limit of 2.4 μmol L−1, free from the interference of ascorbic acid, urea and uric acid, compounds typically found in biological samples. The sensor was assembled in a portable electrochemical system that enables fast (160 injection h−1), precise (RSD < 5%) and selective determination of glucose without the need of enzymes (electrocatalytic properties of the Ni-G-PLA nanocomposite). The obtained results showed that Ni-G-PLA is a promising material for the production of disposable sensors for selective detection of glucose using a simple and low-cost 3D-printer.

Single crystal synthesis of nickel micro-particles with effective involvement of surfactants

Single-crystal nickel micro-particles have been synthesized using oleylamine which perform both functions, as solvent and as reductant, along with nickel nitrate hexahydrate as the metallic salt and C-TAB as a surfactant. SEM imaging and X-ray techniques were used to confirm the presence of the single-crystal structure of nickel micro-particles. The effect of crystallinity on field-based and especially temperature based magnetic properties resulting in higher curie temperatures of nickel micro-particles was also analyzed. Their morphology and magnetic properties were compared with commercially obtained nickel micro-particles and a variety of other nickel microparticles prepared by using different surfactants in the same system.

2D rotary sensor based on magnetic composite of microrods

This study presents a two-dimensional rotary sensor employing the impact of an externally exposed magnetic field on the inductance of coils with cores composed of suspended magnetic microrods. A mixture of polydimethylsiloxane and nickel microparticles in the average size of about 8–20 µm was utilized as the inductor coil. Interestingly, the variations in the coils’ inductance were effectively used to sense the rotations in both azimuth and elevation. A readout circuit was designed to convert the coils’ inductance to voltage and demonstrated a conversion coefficient of 8.6 mV/° in azimuth and 19.1 mV/° in elevation. Due to the inexpensive utilized material and relatively simple fabrication process, the proposed rotary sensor can be a great candidate for this application.

Palladium Deposition on Nickel Microparticles by a Galvanic Replacement Reaction for Electrocatalytic Oxidation of Ethanol

Palladium was deposited or modified on nickel microparticles (NiMPs) via a galvanic replacement reaction between tetrachloropalladate (PdCl42–) and NiMPs by simply dispersing NiMPs in an aqueous solution of 1.0 mM PdCl42–. Because Pd modified NiMPs (Pd/NiMPs) reasonably exhibit characteristic electrochemical responses coming from Pd for ethanol oxidation in alkaline media, Pd deposition on NiMPs could be evaluated by measuring cyclic voltammograms of 1.0 M ethanol in 1.0 M NaOH aqueous solution with a Pd/NiMPs modified glassy carbon (GC) electrode. For three kinds of commercially available NiMPs and one kind of Ni nanoparticles (NiNPs), we performed the Pd deposition and observed the differences of the electrocatalytic responses for ethanol oxidation. SEM and EDS analyses were also performed to discuss the relationships between the Pd deposition and electrocatalytic responses. Consequently, it was found that compared with spherical NiMPs, irregular-shaped NiMPs and/or NiMPs having rugged surfaces were suitable to the modification of Pd by capturing PdCl42– in the reaction solution effectively. The maximum current of the ethanol oxidation with Pd/NiMPs per the Pd amount was over 1000 mA mg(Pd)−1, assuming that all PdCl42– were captured by the galvanic replacement reaction. The present results show that NiMPs have substantial potential as supporting materials of electrocatalysts for ethanol oxidation.

Voltage-Controlled, Nonreciprocal Millimeter-Wave Propagation From Magnetoelastic Membranes Infused With Aligned Nickel Microparticles

Differential Faraday rotation of the linear polarization of millimeter-wave (mmW) Gaussian beams has been observed from a magnetoelastic material system consisting of a silicone membrane that was infused with aligned nickel microparticles, mounted to a piezoelectric annulus, and immersed in a static magnetic field. The piezoelectric crystal was driven near its radial mode of resonance by an ac voltage signal so as to periodically stretch the membrane about the axis of mmW propagation. The stretching modulated the distribution of nickel microparticles and resulted in a change in magnetic properties of the material, specifically the effective Verdet constant. A customized, quasi-optical apparatus was phase locked with the ac driving signal to determine the difference in Faraday rotation due to the stretched and un-stretched states of the membrane.