Nano-sized Nickel Research Articles

Thermal Decomposition of 3-Nitro-1,2,4-Triazole-5-One (NTO) and Nanosize NTO Catalyzed by NiFe2O4

Nanosize Nickel ferrite (NiF) was synthesized by the co-precipitation methods, and its effect as a 5% by mass additive was studied on the thermal decomposition of micrometer and nanometer size NTO. In the presence of a 5% NiF additive, the thermal decomposition peak temperature of NTO was decreased from 276.36 to 260.18 °C and that of nanoNTO was decreased from 261.38 to 258.89 °C (β = 10 °C min−1). The kinetics parameters confirm the catalytic activity of NiF for the thermal decomposition of NTO, and nNTO as the parameters such as activation energy (NTO = ~ 25.45% and nNTO = ~ 45.94% decrement), and pre-exponential factor (NTO = ~ 21.94% and nNTO = ~ 43.12% decrement) were decreased when 5% NiF additive was added to NTO, and nNTO. The rate of the decomposition process was increased in the presence of a 5% NiF catalyst, indicating the faster thermal decomposition of both NTO, and nNTO in the presence of a nickel ferrite catalyst.

Ultrafast sodium-ion storage in an interconnected Ni/Ni3S2 nanocomposite with long-term cycling performance

Nickel sulfide (Ni3S2) is a potential anode candidate for sodium-ion batteries due to its abundance, stable structure, and low price. However, its rate and cycling performance require improvement for practical applications. This paper reports the facile synthesis of a unique composite consisting of an interconnected nickel/nickel sulfide nanocomposite (Ni/Ni3S2) by heating a mixture of nickel nanopowder and sulfur. The interconnected nanostructured backbone of the nickel nanoparticles facilitates continuous electron pathways in the composite, while the embedded nanosized nickel sulfide domain reduces the diffusion length and improves reaction kinetics. The Ni/Ni3S2 electrode exhibits excellent rate performance in dimethyl ether (DME) electrolyte, with a current density of 80 A g−1 and capacity of 151 mA h g−1; it also exhibits stable, ultralong cycling performance. Synergism between the unique nanostructure of the composite and the low-viscosity DME electrolyte may be responsible for the extraordinary cycling and rate performance. A full cell with a Na3V2(PO4)3 (NVP) electrode delivers a capacity of 111 mA h g−1 at 100 A g−1; moreover, the Ni/Ni3S2–NVP full cell retains 55% of its capacity after 5000 cycles at 20 A g−1. The developed strategy, which uses a conductive metal-nanoparticle/metal-sulfide nanocomposite, is applicable to other systems and is scalable for practical applications.

Thermal decomposition and kinetic investigation of AP and AP based composite solid propellant in the presence of nickel ferrite additive

Nanosize nickel ferrite (NiF) with an average crystalline size of 28.6 nm has been successfully synthesized via the co-precipitation method. NiF was found to efficiently reduce the thermal decomposition of ammonium perchlorate (AP) and Composite solid propellants (CSPs) along with an increment in the burning rate of CSPs by 1.6 times. The high-temperature DSC exothermic decomposition peak of AP was decreased by 59.04 °C in the presence of 1% by weight NiF additive. Differential Scanning Calorimeter (DSC) exothermic peak of CSPs based on AP + NiF was decreased by 37.72 °C as compared to that of CSPs based on pure AP. Further, the kinetics parameters of AP and AP + NiF mixture were evaluated using iso-conversional methods. The results indicated that the activation energy the of AP + NiF mixture was increased despite reduction in the thermal decomposition temperature.

Effects of nano filler powder during microwave-based joining of SS304 butt joints

Filler powder plays an important role during microwave hybrid heating-based joining process. In this work, nano-size nickel powder has been taken as filler material for preparing SS304-SS304 butt joints. Effects of size of nickel powder on mechanical properties (strength and hardness) of joints have been investigated. Scanning electron microscope tests show that the joints possess uniform microstructure. Energy dispersive spectroscopy tests demonstrated the presence of elements (Chromium, iron, carbon, silicon, manganese, phosphorus) other than filler powder (Nickel) in the joint region thereby confirming complete melting of joint region and also transfer of carbon from graphite separator sheet to joint region during microwave processing. Micro-hardness test results showed that nano-size filler powder-based joints are less prone to surface wear than corresponding micro-size filler powder-based joints. Micro-tensile strength of nano-size nickel powder-based joints is also far better than micro-size filler powder-based joints.

The effect of different atmosphere treatments on the performance of Ni/Nb–Al2O3 catalysts for methane steam reforming

Methane steam reforming is currently the most widely used hydrogen production reaction in industry today. Ni/Nb–Al2O3 catalysts were prepared by treatment under H2, N2, and air atmosphere prior to reduction and applied for methane steam reforming reaction at low temperature (400–600 °C). The hydrogen-treated catalysts increased catalytic activity, with 55.74% methane conversion at S/C = 2, GSVH of 14400 mL g−1 h−1 and 550 °C. The H2 atmosphere treatment enhanced the Ni–Nb interaction and the formation of stable, tiny, homogeneous Ni particles (6 nm), contributing to good activity and stability. In contrast, the catalysts treated with nitrogen and air showed weaker interactions between Ni and Nb species, whereas the added Nb covered the active sites, which caused the decrease in activity. Meanwhile, carbon accumulation was also observed. This work is informative for preserving small nano-sized nickel particles to enhance catalytic performance.

Investigation of gamma-rays and fast neutrons attenuation parameters for NixCo1-xFe2O4 nickel ferrites

The present work aims to study the radiation shielding parameters of new composite nickel ferrites in micro and nano-size. Synthesis of nickel-nano ferrites was carried out using the chemical co-precipitation technique. The measurement of gamma shielding parameters for nano-sized nickel ferrites was done experimentally. In addition, the calculations of the shielding parameters for the micro-sized nickel ferrites were carried out using FLUKA-Monte Carlo and WinXCom software. The shielding parameters were given in terms of mass and linear attenuation coefficients, half and tenth-value layer, mean free path, effective atomic number, and effective density of electrons values. Besides, the build-up factor and its parameters were calculated for the proposed shielding material. Fast neutrons effective removal cross-sections were also estimated for the NiCoFe2O4 composite at different Ni/Co ratios. It was found that the highest nickel content (W4), the best gamma radiation attenuation parameters for the proposed composite, with a slight difference between nano and micro-sized samples. The maximum obtained value of mass attenuation coefficient at 661.7 keV was 0.0753 and 0.0751 (cm2/g) for nano- and micro-sized ferrite samples. Furthermore, the highest fast neutron removal cross-section was 0.1562 cm−1 which was achieved with the highest cobalt content sample (W1).

Formation of NiMoO4 Anisotropic Nanostructures under Hydrothermal Conditions

—The synthesis of NiMoO4 hierarchical nanostructures using the hydrothermal method has been studied. The decomposition of NiMoO4·xH2O crystalline hydrate formed during the synthesis has been studied using synchronous thermal analysis upon heating in a stream of air and argon. According to X-ray diffraction as well as scanning and transmission electron microscopies, the proposed conditions allow one to synthesize single-phase nanosized (average CSR size of about 25 ± 2 nm) nickel(II) molybdate, which has a spinel-type monoclinic structure (space group C2/m) without impurity inclusions.

Correction to: Investigation of the Process of Synthesizing Nanosized Nickel Powders by Hydrogen Reduction under Nonisothermal Conditions

Correction to: Investigation of the Process of Synthesizing Nanosized Nickel Powders by Hydrogen Reduction under Nonisothermal Conditions

Structural and optical properties of TiO2:NiO nanoparticles thin films prepare by chemical spray pyrolysis

The properties of structural and optical of pure and doped nano titanium dioxide (TiO2) films, prepared using chemical spray pyrolysis (CPS) technique, with different nanosize nickel oxide (NiO) concentrations in the range (3-9)wt% have been studied. X-Ray diffraction (XRD) technique where using to analysis the structure properties of the prepared thin films. The results revealed that the structure properties of TiO2 have polycrystalline structure with anatase phase. The parameters, energy gap, extinction coefficient, refractive index, real and imaginary parts were studied using absorbance and transmittance measurements from a computerized ultraviolet visible spectrophotometer (Shimadzu UV-1601 PC) in the wavelengths range (300-800)nm. Optical properties of TiO2 affected by the adding of NiO impurity where the transmittance increased as NiO concentration increased but with more adding the transmittance returned to decrease again. It was found the extinction coefficient, refractive index, real and imaginary parts values decreased with increasing doping percentage up to 7% and then increases occur one more again at 9%. Energy gap values increased after doping with NiO where the values lies in the range was 3.31 to 3.51 eV .

Large Scale Synthesis of Manganese Oxide/Reduced Graphene Oxide Composites as Anode Materials for Long Cycle Lithium Ion Batteries

Manganese oxides have been frequently used as cathodes in primary batteries. Applications of manganese oxides in secondary batteries are limited by low electrical conductivity and rapid capacity fading because of electrode pulverization and aggregation. In this study, a solid-state synthetic strategy is presented that successfully combines nanosize (∼50 nm) nickel doped α-MnO2 with reduced graphene oxides as highly stable composite anodes in lithium ion batteries. The synthesis approach is easy to scale up and suitable for industrial applications. The rationally designed Ni-α-MnO2/RGO was tested in galvanostatic half coin cells for Li+ charge–discharge studies. The results show that this composite maintains a high capacity of 615 mAh g–1 even after 200 cycles at a high current rate of 1 C (830 mA g–1), and with a high Coulombic efficiency near 99%. The anodes exhibit excellent rate capability in a wide range of rate testing from 0.2 to 10 C, without showing capacity decay. This superior anode performance is ascribed to the reduced size of α-MnO2 domains that are well dispersed in an RGO matrix, which affords good ionic/electrical conductivity, low charge transfer resistance and mitigates issues of volume expansion of the anodic active materials. This study opens up an avenue for developing the manufacturing of high-performance electrodes for real applications, such as batteries in electrical vehicles.

Hydrolysis of Methoxylated Nickel Hydroxide Leading to Single-Layer Ni(OH)2 Nanosheets

Various methods for the preparation of inorganic nanosheets have been established and they have contributed to the substantial development of the research on diverse two-dimensional materials. Covalent surface modification of layered metal hydroxides with alkoxy groups is known to effectively weaken the interactions between layers, although the modified ligands are irreversibly immobilized. This study proposes the use of methanol as a removable surface modifier forming monodentate alkoxy bonds to prepare nickel hydroxide nanosheets through hydrolysis. Methoxylated layered nickel hydroxide, consisting of randomly stacked nano-sized nickel hydroxide sheets (10-20 nm in size) having Ni-OCH3 groups on its surface, was synthesized in a powder form through the precipitation reaction of a nickel salt in methanol at room temperature. After dispersing the aggregated methoxylated nickel hydroxide in water, single-layer nickel hydroxide nanosheets with a thickness of 1.2 nm and a lateral size of 460 nm at maximum, which is larger than the size of original methoxylated nickel hydroxide were found in the suspension. The time-course experiments during hydrolysis suggested that two-dimensional crystal growth of exfoliated nickel hydroxide sheets proceeded, resulting in the formation of the nanosheets. Moreover, single-layer and nano-sized cobalt hydroxide was prepared through a similar manner. This work demonstrates that two-dimensional alkoxides consisting of polymeric M-O-M bonds are useful precursors for the design of metal-hydroxide-based nanomaterials.

Investigation of the Process of Synthesizing Nanosized Nickel Powders by Hydrogen Reduction Under Nonisothermal Conditions

Investigation of the Process of Synthesizing Nanosized Nickel Powders by Hydrogen Reduction Under Nonisothermal Conditions

Fabrication of homogeneous nanosized nickel powders using a planetary ball mill: Applications to multilayer ceramic capacitors (MLCCs)

Given the increasing demand for multilayer ceramic capacitors (MLCCs) for miniaturization of electronic parts, a narrow nanoparticle size distribution is crucial to optimize MLCC performance and stability. We explored the sintering behavior of nickel powder with the goal of controlling particle size. A micro-sized nickel oxide powder was milled to uniform size (183.2 ± 53.8 nm) using a planetary ball mill; the size distribution was more uniform than that of a commercial powder (400.2 ± 183.4 nm). The sintering characteristics and capacitive features of the powders were analyzed after reduction in hydrogen. We found that the milled powder, with a narrow particle size distribution, exhibited delayed sintering rate, which paralleled the shrinkage of the of BaTiO3 layer. Discrete layers were thus obtained. Moreover, use of the milled powder reduced capacitance noise by 25% compared to that when other powders were employed; our milled powder contributed to the formation of stable electrodes.

Activated carbon fibers via reductive carbonization of cellulosic biomass for adsorption of nonpolar volatile organic compounds

Reductive carbonization of cellulosic fibers via nano-sized nickel catalyst in the presence of hydrogen was examined for production of activated carbon fibers (ACFs). The results showed that 99.5 % of oxygen originally presented in the biomass was removed as measured by using X-ray Photoelectron Spectroscopy (XPS), with over 63 % carbon in form of reductive species. Such reductive ACFs demonstrated high adsorption capacities for non-polar volatile organic compounds (VOCs). Particularly, the reductive ACFs absorbed benzene at a capacity that was 8 times higher than traditionally prepared carbon fibers. That can be attributed to both the reductive surface chemistry and morphology generated by the activity of the nanocatalysts. The unique network structure of the ACFs also provided a fine conductivity, that made it possible for efficient material regeneration via electrothermal desorption. The absorbed VOCs could be completely released within 1 min upon application of a moderate electrical current, and the regenerated materials could regain 100 % of its adsorption capacity even after repeated adsorption and desorption cycles. This work demonstrated for the first time the use of nanocatalyst-assisted reductive carbonization in manipulating surface properties of bio-based carbon materials, promising the production of a new class of carbon materials for industrial applications including air quality control, gas separation, and fuel storage.

Colloidal processing and sintering of WC-based ceramics with low Ni content as sintering aid

To soften the extreme sintering conditions of Tungsten Carbide (WC), a 3 wt.% of metallic nickel (Ni) was added to the starting powders. To ensure a fair distribution of the second phase and an intimate mixture of the phases, the colloidal process was adopted. A commercial Ni and a in-house synthesised nanosized nickel were used as sintering aids. Rheological studies allowed a high dispersion of the nickel in the final composite powders. Sintering studies by Hot-Pressing route (HP) proved the great benefices of Ni as a sintering aid, decreasing the maximum temperature necessary to achieve full densification, from 1900 to 1450 °C and dwell times from 20 to 7 min. Among all the materials obtained, the best results in terms of density, microstructure and properties were obtained for WC-nNi, which achieved hardness of 14.8 GPa and toughness comparable to conventional cermets with much higher content of metallic phase.

Nickel hydroxide nanoparticles decorated napthalene sulfonic acid-doped polyaniline nanotubes as efficient catalysts for nitroarene reduction

Nanosize nickel hydroxide decorated 2-napthalene sulfonic acid-doped polyaniline nanotubes nanocomposites (Ni(OH)2@NSA-PANI NCs) were successfully developed for the catalytic reduction of aromatic nitro compounds. The Ni(OH)2@NSA-PANI NCs were synthesised by depositing Ni(OH)2 nanoparticles onto 2-napthalene sulfonic acid doped PANI nanotubes surface. The resulting material was characterized using field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), powder X-ray diffraction (P-XRD), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The prepared nanocomposite showed a remarkable ability to catalytically hydrogenate aromatic nitro compounds using sodium borohydride (NaBH4) as hydrogen source in aqueous medium at room temperature. Kinetic studies were performed using 4-nitrophenol (4-NP) as the model substrate, using the Langmuir-Hinshelwood model. The catalyst showed pseudo-first-order kinetics, with rate constants estimated between 0.08287 and 0.3649 min−1. Catalyst recyclability without reduced activity was demonstrated over 10 successive cycles. The optimised nanocomposite catalyst demonstrated a low activation energy barrier towards 4-NP reduction.

Ni2P/graphitic carbon nanostructure electrode with superior electrochemical performance

Because of their high theoretical specific capacities, transition metal phosphides have been interested as promising anode candidates for lithium-ion batteries. However, high irreversible capacity reduction and pulverization of the transition metal phosphide structure caused by volumetric expansion during cycling obstruct the commercialization of transition metal phosphides as an anode for lithium-ion batteries. In this study, we fabricated a nanostructured electrode consisting of nano-sized nickel phosphide (Ni2P) and high-crystalline carbon (Ni2P/C) using a chemical vapor deposition method and phosphidation process. The improved capacity and rate cycling performance of Ni2P/C, i.e. 324 mAh g−1 at 200 mA g−1 after 200 cycles and 135 mAh g−1 at 1600 mA g−1, might be attributed to the relief of volumetric expansion and prevention of pulverization caused by the surrounding graphitic carbon structure in the vicinity of Ni2P nanophase.

Nickel Nanoparticle-catalyzed Carboxylation of Unsaturated Hydrocarbon with CO2 Using Sulfur-modified Au-supported Nickel Material

A hydrocarboxylation reaction of alkyne or styrene derivatives with CO2 proceeded smoothly by using an air-stable nano-sized nickel catalyst supported on sulfur-modified gold (SANi), giving functio...

Synthesis of Nanosized Nickel Particle from Spent Cathodic Material Containing Lithium

Due to the rapid development of electricity, electronics, information communication, and biotechnology in recent years, studies are actively being conducted on nanopowders as it is required not only for high strengthening but also for high-function powder with electric, magnetic, and optical properties. Nonetheless, studies on nickel nanopowders are rare. In this study of the synthesis of nickel nanoparticles from LiNiO2 (LNO), which is a cathode active material, we have synthesized the nanosized nickel powder by the liquid reduction process of NiSO4 obtained through the leaching and purification of LNO. Moreover, we have studied the reduction reaction rate according to the temperature change of liquid phase reduction and the change of particle size as a function of NaOH addition amount using hydrazine monohydrate (N2H4·H2O) and NaOH.

Nanoscale nickel metal organic framework decorated over graphene oxide and carbon nanotubes for water remediation

In this report, highly crystalline and well-dispersed nano-sized nickel metal organic framework (MOFs) was decorated over graphene oxide (GO) and carbon nanotubes (CNTs) platforms to form hybrid nanocomposites. These as-synthesized hybrid nanocomposites were synthesized through a one-pot green solvothermal method. The prepared nanocomposites were characterized by SEM, TEM, EDS, XRD, FT-IR, Raman and TGA techniques. XRD analysis revealed the crystalline structure of the hybrid nanocomposites. Morphological and elemental studies also verified successful decoration of nickel-benzene dicarboxylate (Ni-BDC) MOFs over GO and CNT platforms. Chemical analysis collected through IR, and thermal analysis collected through TGA technique, illustrated the presence of all the components in the hybrid nanomaterials. Methylene blue (MB) was used as a model organic pollutant to analyze the adsorption capacity of the prepared nanocomposites. According to the findings, a strong interaction exists between the MB molecule and the developed adsorbents at which due to the synergistic effect, the hybrid nanocomposites show several times higher adsorption capacity compared to that of parent materials. This improvement can be due to several reasons: high surface area of the MOFs in the composites resulting from the smaller size of MOFs, presence of the pores formed between the MOFs and the platforms and different morphological characteristic of Ni-BDC MOFs in hybrid nanocomposites, compared to bare Ni-BDC MOFs. Furthermore, the isotherm and kinetic studies revealed that the adsorption of MB onto the newly prepared adsorbents could best be explained by the Langmuir and Pseudo-second order kinetic models. A regeneration study demonstrated the highly stable nature of the hybrid nanocomposites.