Ni Salts Research Articles

Phase transformations in the nickel phosphide system induced by transition-metal doping and their electro-catalytic study

Nickel phosphides were formed from Ni salt in TOPO/TOP or HDA/TOP and phase transformations from Ni2P to Ni5P4 and vice versa was observed by doping with Cu or Mn salts. Doping effect on phase transition and electrocatalytic properties is studied.

Sulfur-DMSO promoted oxidative coupling of active methylhetarenes with amines: access to amides.

The elemental sulfur-DMSO couple was found to efficiently promote the oxidative coupling of active methylhetarenes with amines to yield amides under simple heating conditions. When 2-methylquinoline was used as the methylhetarene component, the formation of the expected 2-quinolinecarboxamides from anilines could be efficiently catalyzed by iron, nickel and cobalt salts. The method displayed good functional group tolerance and was applicable to aromatic, heteroaromatic and aliphatic amines. Other substrates such as phenylacetic acid, dibenzyl disulfide, and benzylamine could act as competent partners in place of methylhetarenes.

Antimicrobial, Cytotoxicity and Molecular Docking Study of New Quinoline Schiff Base and its Metal(II) Complexes

A new quinoline Schiff base ligand was synthesized by the reaction of 2-hydroxy-7-methylquinolin- 3-carbaldehyde and 4-methylbenzene sulfonohydrazide. Synthesized Schiff base further utilized for the formation of stable metal complexes with Cu(II), Ni(II), Co(II) and Cd(II) metal salts and characterized by different spectroscopic techniques i.e. 1H NMR, 13C NMR, FT-IR, UV-visible, ESR, MASS and TGA. The low molar conductance values indicate that synthesized metal(II) complexes were non-electrolytes. The magnetic moment value indicates that Cu(II), Ni(II) and Co(II) complexes were paramagnetic. Further, these compounds were screened for inhibition activity against four bacterial strains, three fungal strains and cytotoxicity against the A-549 and MCF-7 cell lines by using the MTT method. Among the synthesized complexes, metal complexes exhibited excellent anticancer activity against the human lung cancer cell line (A-549). Schiff base and its Cd(II) complex showed good antibacterial activity. Furthermore, molecular docking study shows the significant binding affinity of metal complexes with tubulin protein. Present study proposed that all the synthesized Schiff base metal(II) complexes have excellent biological activity and could be act as potential anticancer agents.

SYNTHESIS, SPECTRAL, THERMAL AND ANTIMICROBIAL STUDIES OF NEW METAL COMPLEXES OF SUBSTITUTED HYDROXY PROPIOPHENONE

A new series of metal complexes of innovative bisketimines (L1 - L5) have been synthesized. Schiff base ligands were synthesized by condensing substituted 2’- hydroxy propiophenone and ethylene diamine. The synthesized Schiff bases act as tetradentate ligands with two nitrogen and two phenolic oxygen groups and co-ordinates with Co (II), Ni (II), Cu (II) and Zn (II) salts. Ligands and their metal complexes have been studied using 1H NMR, IR, UV-Vis and thermogravimetric techniques. The complexes were crystalline, according to the XRD pattern. The thermogravimetric data revealed the thermal stability of the complexes. The study of antibacterial and antifungal activities of the ligands and their metal complexes showed more effectiveness of metal complexes than Schiff base ligands.

Nickel(II)-Complex of Ceftibuten Dihydrate: Synthesis, Characterization and Thermal Study

Ceftibuten dihydrate is a semisynthetic, orally administered, third generation cephalosporin antibiotic which is effective against most of the pathogens causing infections in the respiratory tract. Complexation of ceftibuten dehydrate (Ligand, L) was performed with hydrated Ni(II) salt (Metal, M) in the ratio of 2:1 (L:M) in aqueous medium at 90 oC. The metal complex was then characterized by spectral techniques and thermal analyses. The FT-IR spectral data of metal complex suggested the monodentate bonding of metal ion to carboxylate group. Spectral evidence also supported the formation of five-membered ring via coordination of metal ion to β-lactam nitrogen and carboxylate group of parent drug. Thermal behavior of ligand and complex were studied. Thus, thermoanalytical (DSC and TGA) results also supported the formation of new metal complex, indicating the successful interaction of metal ion to ligand. Dhaka Univ. J. Pharm. Sci. 20(2): 219-225, 2021 (December)

A mild aqueous synthesis of ligand-free copper nanoparticles for low temperature sintering nanopastes with nickel salt assistance

An organic ligand-free aqueous-phase synthesis of copper (Cu) nanoparticles (NPs) under an air atmosphere was successfully achieved by reducing copper(II) oxide particles with a leaf-like shape in the presence of Ni salts at room temperature. The resulting Cu NPs with a mean particle diameter of ca. 150 nm exhibited low-temperature sintering properties due to their polycrystalline internal structure and ligand-free surface. These Cu NPs were applied to obtain Cu NP-based nanopastes with low-temperature sintering properties, and the resistivities of the obtained Cu electrodes after annealing at 150 °C and 200 °C for 30 min were 64 μΩ∙cm and 27 μΩ∙cm, respectively. The bonding strength between oxygen-free Cu plates prepared using the Cu NP-based nanopastes reached 32 MPa after pressure-less sintering at 260 °C for 30 min under a nitrogen atmosphere. The developed manufacturing processes using the developed Cu nanopastes could provide sustainable and low-CO2-emission approaches to obtain Cu electrodes on flexible films and high-strength bonding between metal plates as die-attach materials for power devices under energy- and resource-saving conditions.

One Pot Ultrasonic Assisted {[Ni(tptz)Cl(H2O)2][Ni(tptz)(H2O)3]}-3Cl.5H2O Complex Formation Using Triazine Ligand, XRD/HSA-Interactions, and Spectral and Thermal Investigation

Under room temperature ultrasonic conditions, mixing the neutral 2,4,6-tri(pyridin-2-yl)-1,3,5-triazine (tptz) ligand with Ni(II) salt resulted in the preparation of a unique {[Ni(tptz)Cl(H2O)2]-[Ni(tptz)(H2O)3]}3Cl.5H2O complex with two different nickel(II) centers in a high yield. The crystal structure of {[Ni(tptz)Cl(H2O)2][Ni(tptz)(H2O)3]}3Cl.5H2O revealed the existence of distorted octahedral around both Ni(II) centers. The complex structure was further supported by FT-IR, UV-Vis., CHN-EA, TGA and EDX. The computed HSA was also performed to support the XRD interaction types. The existence of the H2O molecules in the crystal lattice was examined by FT-IR and TG/DTG measurements that proved the presence of coordinated and uncoordinated water molecules. Moreover, the thermal stability of the desired complex was evaluated at open atmosphere via TG/DTG and showed stability up to ~400 °C and multistep thermal decomposition.

Efficient OER nanocomposite electrocatalysts based on Ni and/or Co supported on MoSe2 nanoribbons and MoS2 nanosheets

It is well known that the benchmark electrocatalysts for OER in alkaline solution are RuO2 and IrO2; however, the high cost, scarcity, and instability of these metal oxides impede their ample use in OER processes, and this has fueled the search for cheap Earth-abundant elements which are equally efficient for application as electrocatalysts in OER. The present work reports the use of hydrothermal and calcination methods for the synthesis of nanocomposites made up of Ni and/or Co salts and urea in combination with MoSe2 and MoS2 and their application as efficient and stable electrocatalysts for OER in alkaline solution. The NiCoMoSe, NiCoMo, CoMoSeS, and CoMo nanocomposites constructed in the present study presented high OER electrocatalytic activity and stability mainly as a result of the following: the combination of N atoms bonded to Ni and/or Co (and Mo); the electrons released from the oxidation of Co from the 2+ to 3+state, Ni oxidation from the 2+ to 3+state, and Mo oxidation from the 4+ to 6+state; and the metal oxides (CoMoO4, NiCo2O4, Co2Mo3O8, and Co3O4) supported on MoS2 nanosheets and MoSe2 nanoribbons which contributed to a decrease in charge transfer resistance, apart from keeping the ECSA values relatively low.

Synthesis, structure and properties of tris(hydroxymethyl)aminomethane complexes with biogenic metal salts

New coordination compounds - analogues of hydrometallatranes, characterized by FT-IR spectroscopy, mass spectrometry and elemental analysis, were synthesized by the interaction of tris(hydroxymethyl)aminomethane (TRIS) with Cu(II), Co(II), Ni(II) and Zn(II) salts of carboxylic acids. The crystal structure of TRIS complex with Cu(II) cinnamate was determined by X-ray diffraction. The structural parameters and gap energy for this complex have been calculated by the DFT method. The thermal analysis data for new TRIS complexes are presented. The effect of some TRIS hydrometallatranes, as well as TEA and TPA hydrometallatranes on the growth of corrosion-aggressive thionic bacteria was studied.

Electrochemical deposition of nickel from aqueous electrolytic baths prepared by dissolution of metallic powder

A new method of preparation of aqueous electrolyte baths for electrochemical deposition of nickel targets for medical accelerators is presented. It starts with fast dissolution of metallic Ni powder in a HNO3-free solvent. Such obtained raw solution does not require additional treatment aimed to removal nitrates, such as the acid evaporation and Ni salt precipitation-dissolution. It is used directly for preparation of the nickel plating baths after dilution with water, setting up pH value and after possible addition of H3BO3. The pH of the baths ranges from alkaline to acidic. Deposition of 95% of ca. 50 mg of Ni dissolved in the bath takes ca. 3.5 h for the alkaline electrolyte while for the acidic solution it requires ca. 7 h. The Ni deposits obtained from the acidic bath are physically and chemically more stable and possess smoother and crack-free surfaces as compared to the coatings deposited from the alkaline bath. A method of estimation of concentration of H2O2 in the electrolytic bath is also proposed.

Antimicrobial and antifungal properties of NiCu-PANI/PVA quaternary nanocomposite synthesized by chemical oxidative polymerization of polyaniline

Increasing antimicrobial resistance has led to use of novel technologies such as nanomaterials and nanocomposites that have shown effective antimicrobial and/or antifungal activities against several gram-positive and gram-negative bacteria. There have been limited studies on antimicrobial properties of the combined polymer nanocomposites with transitional bimetallic nanoparticles such as nickel (Ni) and copper (Cu). Thus, the main objective of this study was to synthesis, characterize and investigate the antibacterial and antifungal properties of NiCu-PANI/PVA nanocomposite. The nanocomposite films with different amount of Ni and Cu salts were synthesized by chemical oxidative polymerization of polyaniline using HCl as oxidant and PVA as a stabilizer. Optical, chemical composition, and morphological characteristics as well as thermal stability were evaluated using UV–Visible, FTIR, SEM-EDX, and TGA analyses. Antimicrobial properties were then determined using the disc diffusion assay against gram-negative bacteria (i.e., Escherichia coli ATCC 25922, Klebsiella pneumonia ATCC 700603, Proteus sp.,) and gram-positive bacteria (i.e., Staphylococcus aureus ATCC 2593). Fungal plant pathogens including Aspergillus niger and Fusarium oxysporum f. sp. pisi were also evaluated for determination of antifungal activity of NiCu-PANI/PVA films. Among the synthesized films, Ni65Cu35-PANI/PVA showed excellent antibacterial activity against all the bacteria strains examined in this study. The diameters of inhibition zones for Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, Proteus sp., and Staphylococcus aureus ATCC 2593 were 23, 23, 17, and 18 mm, respectively indicating good antibacterial activities. Additionally, NiCu-PANI/PVA, particularly the films with higher Cu intake, showed better antifungal activity against Fusarium oxysporum f. sp. pisi. However, NiCu-PANI/PVA was ineffective against Aspergillus niger.

Nickel(II) complexes of two potentially heptadentate(N7) Tripodal Schiff-base ligands; X-ray crystal structure and theoretical studies

In absolute methanol, one equivalent of tripodal tetraamines bis(3-aminopropyl)(2-aminoethyl)amine, ppe or (3-aminopropyl)-bis(2-aminoethyl)amine, pee condenses with three equivalents of 2-pyridinecarboxaldehyde. Upon the addition of Ni(II) salt to the solutions of produced Schiff base ligands, two new Schiff-base complexes, [Ni(py3ppe)](ClO4)2, (1), and [Ni(py3pee)](ClO4)2, (2), were prepared. Both complexes 1 and 2 were characterized by X-ray crystal structure analysis, CHN elemental analysis and FT-IR spectroscopy. The data show that both complexes have a distorted trigonal antiprism geometry for Ni(II) ion, in which the tertiary nitrogen atom has been not coordinated to the central metal ion. A DFT theoretical study at bp86/def2-tzvp level of theory on a series of this type of Ni(II) complexes shows that, interestingly, the values of metal–ligand interaction energies are very similar and are about 510 ± 2 kcal mol−1.

Diboron-Promoted Reduction of Ni(II) Salts: Precatalyst Activation Studies Relevant to Ni-Catalyzed Borylation Reactions

Diboron-Promoted Reduction of Ni(II) Salts: Precatalyst Activation Studies Relevant to Ni-Catalyzed Borylation Reactions

Oriented Nanosheet-Assembled CoNi-LDH Cages with Efficient Ion Diffusion for Quasi-Solid-State Hybrid Supercapacitors.

Fast-charged energy-storage technologies have become important nowadays as they are required by many applications, including automobiles. This inspires the exploitation of hybrid supercapacitors (HSCs) with the advantages of fast charge offered by the capacitor characters and high energy density from the property of battery technology. The challenges lay in the construction of advanced materials with high pseudocapacitive activity. Herein, a metal-organic framework derivative is utilized to address the problems. Specifically, polyhedral CoNi layered double hydroxide (CoNi-LDHx) cages assembled in the form of nanosheet arrays are prepared from ZIF-67 using a facile ion-exchange approach. Based on the control over the mass ratio of ZIF-67 to Ni salt, the optimal CoNi-LDH2 is attained. It exhibits ultrahigh capacities ranging from 1031.4 to 667.3 C g-1 under 1-25 A g-1, thanks to rich Faradaic active spots and the accelerated kinetics provided by the synergy between nanosheet arrays and the hollow structure. The CoNi-LDH2-based HSC with the gel electrolyte shares remarkable energy output of 49 Wh kg-1 and approving cyclability with almost no capacity decay after 12 000 cycles. This is an advancement vs many related studies and can arouse tremendous interests of researchers in solving the main problems of energy storage.

Nickel nanoparticles encapsulated by nitrogen-doped bamboo-shaped carbon nanotubes with a high-level doping: A boosting electrocatalyst for alkaline hydrogen evolution

The development of highly active and stable alkaline hydrogen evolution electrocatalysts is highly desired in the field of clean energy. Herein, we chose urea and nickel chloride as precursors, and synthesized metallic Ni nanoparticles encapsulated by nitrogen-doped bamboo-shaped carbon nanotubes through one-pot calcination at low temperature (550 °C). Along with the increase in the amount of Ni salt, the electrocatalyst support has undergone a transformation from polymeric carbon nitride to nitrogen-doped carbon, and the charge transport ability and electrochemical active surface area of the electrocatalysts have been significantly improved. For the optimized Ni/NC-0.35 electrocatalyst with 13.42 wt% nitrogen-doping level, the overpotential at cathodic current density of 10 mA cm−2 is 133 mV (vs. RHE) in alkaline electrolyte, the corresponding Tafel slope is 109 mV dec-1, and there is no significant decrease in hydrogen evolution activity after 16 h. The boosting activity can be attributed to the synergistic effect of the mixed phase Ni nanoparticles, the high nitrogen-doping level and the bamboo-shaped carbon nanotube structure towards the alkaline hydrogen evolution reaction. This work provides a new way for the design of high-activity alkaline hydrogen evolution electrocatalysts and the facile synthesis of high nitrogen-doping carbon-coated metal nanoparticle catalysts.

Nickel-Catalyzed Reductive Asymmetric Aryl-Acylation and Aryl-Carbamoylation of Unactivated Alkenes

Nickel-Catalyzed Reductive Asymmetric Aryl-Acylation and Aryl-Carbamoylation of Unactivated Alkenes

Bilayered NiZn(CO3)(OH)2–Ni2(CO3)(OH)2 nanocomposites as positive electrode for supercapacitors

Open architecture and porous NiZn(CO 3 )(OH) 2 –Ni 2 (CO 3 )(OH) 2 bilayers were fabricated on a nickel foam substrate through a two-step processing of Ni and Zn salts under hydrothermal conditions. The initial layer of NiZn(CO 3 )(OH) 2 nanosheets, obtained by alkaline hydrolysis of nickel and zinc salts, was cladded with a top layer consisting of Ni 2 (CO 3 )(OH) 2 nanowire arrays. This double-decker arrangement offered a higher mechanical stability and enhanced electrochemical performance in NiZn(CO 3 )(OH) 2 –Ni 2 (CO 3 )(OH) 2 electrodes, which showed an excellent maximum specific capacitance of 1168.8 F g −1 at 3 A g −1 and superior cycling stability with a capacity retention of ~85.7% after 5000 cycles. Moreover, the asymmetric two-layered NiZn(CO 3 )(OH) 2 –Ni 2 (CO 3 )(OH) 2 //graphene electrodes provided sufficient capacitive energy to turn on a LED light. This superior electrochemical performance is attributed to the hierarchical architecture and large surface area of the composite electrodes that render them in view of facile and scalable synthesis and greater cycling safety as promising candidates for practical applications. • A composite stacked in a unique two-layer structure was fabricated. • This two-layer electrode provide the large surface area for the redox reaction. • As the cycles increased, the electrode became damaged and the capacity deteriorated. • The optimized two-layer electrode improved the retention results after cycle test.

Star iminopyridyl iron, cobalt and nickel complexes: synthesis, molecular structures, and evaluation as ethylene oligomerization catalysts

A novel star iminopyridyl ligand was synthesized in modest yield with 1.0 G star macromolecule and pyridine-2-carboxaldehyde as the raw materials. Reactions of the star iminopyridyl ligand with Fe(II), Co(II) and Ni(II) salts afforded metal complexes (Cat-Fe, Cat-Co and Cat-Ni) in good yields. The compounds were characterized by FT-IR, 1H NMR, 13C NMR, UV–Vis, ESI–MS and ICP-MS. In the presence of methylalumoxane (MAO), the iron, cobalt and nickel complexes have demonstrated higher ethylene oligomerization activity (up to 4.28 × 105 g/(mol Co h)), affording C4 as the major product as well as C6, C8 and C10-18 oligomers. The catalytic activity was quite sensitive to the kind of species. The nature of solvent and co-catalyst significantly affected both the catalytic activity and product distribution. Moreover, the effect of oligomerization parameters (reaction temperature, [Al]/[Co] molar ratio, ethylene pressure) on the catalytic activity and the product distribution was investigated.

Adsorptive and Photocatalytic Properties of Green Synthesized ZnO and ZnO/NiFe2O4 Nanocomposites for Tannery Wastewater Treatment

This study investigated adsorptive and catalytic behaviour of ZnO and ZnO/NiFe2O4 nanocomposites for the removal and degradation of organic pollutants in tannery wastewater. ZnO and ZnO/NiFe2O4 nanomaterials were synthesized via a green method using Zn, Fe and Ni salts precursor and leaves extract of Anacardium occidentale (linn.). Subsequently, the synthesized samples were characterized by different analytical tools. The adsorptive and catalytic performance of the prepared nanomaterial were assessed using reduction in Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Total Organic Carbon (TOC) in tannery wastewater as indicator parameters. High Resolution Scanning Electron Microscope (HRSEM), High Resolution Transmission Electron Microscope (HRTEM), and X-Ray Diffraction (XRD) analysis of ZnO and ZnO/NiFe2O4 confirmed the formation of hexagonal wurtzite nanoparticle and cubic spinel phase with an average crystallite sizes in the range of 13- 28 nm and 30.44 – 42.53 nm respectively. XRD analysis confirmed no change in the polymorph of ZnO upon the addition NiFe2O4. XPS spectrum showed the existence of the elements in the following oxidation state (+2) for Zn, (+1, +2) for Ni and (+2 and +3) for Fe. BET analysis revealed order of the specific surface area of ZnO/NiFe2O4 (44.61 m2/g) > NiFe2O4 (40.39 m2/g) > ZnO (8.91 m2 /g). The adsorptive and photocatalytic results revealed that 3% ZnO/NiFe2O4 exhibits higher efficiency compared to ZnO and NiFe2O4 nanoparticles alone and in the order of 3% ZnO/NiFe2O4 > NiFe2O4 > ZnO. The study revealed that the prepared nanomaterial behaved better as photocatalyst than as nanoadsorbent.
 Keywords: Adsorption, photocatalytic technology; ZnO; ZnO/NiFe2O4, tannery wastewater

SYNTHESIS, COMPLEXATION AND SPECTRAL STUDY OF NOVEL 2-BROMOBENZALDEHYDE DERIVED BENZILMONOXIMEHYDRAZONE

In this newly approached method a novel series of Transition metal complexes were synthesized by the reaction of 2- bromobenzaldehyde react with benzilmonoximehydrazone in ethanolic solution at refluxed condition. Mononuclear complexes were synthesized by reaction with Cu(II), Ni(II) and Co(II) chloride salts. The ligand and its complexes were characterized by elemental analysis, UV, FTIR and PMR spectral studies.