Topic
Nickel
About: Nickel is a research topic. Over the lifetime, 79308 publications have been published within this topic receiving 1210058 citations. The topic is also known as: Ni & element 28.
Papers published on a yearly basis
Papers
More filters
••
TL;DR: In this paper, two-step reaction mechanisms involving adsorbed monovalent intermediate ions for the electrodeposition of iron and nickel as single metals can be combined to form a predictive model for the codeposition of the iron-nickel alloys.
Abstract: Two-step reaction mechanisms involving adsorbed monovalent intermediate ions for the electrodeposition of iron and nickel as single metals can be combined to form a predictive model for the codeposition of iron-nickel alloys. Inhibition of the more noble nickel in the presence of iron is caused by preferential surface coverage of the adsorbed iron intermediate resulting from a difference between the two elements in Tafel constant for the electrosorption step. The role of hydrolyzed cations and surface pH is investigated and methods for evaluating the influence of pH are explored. The analysis shows that changes in surface pH with potential are not necessary for iron-rich (anomalous) deposits, but that variations in pH from one electrolyte to another may influence deposit composition. The tendency toward iron-rich deposits with increasing overpotential exists in all systems, however, and can be prevented only by decreasing the iron concentration of the bath. An extension of the analysis to account for transport limitations in baths with low iron concentration is developed and calculations with the model are presented to illustrate the effects of current density and electrolyte convection under conditions similar to those investigated experimentally in the literature.
219 citations
••
TL;DR: In this paper, a series of α-diimine nickel(II) complexes with bulky camphyl or diaryl-substituted backbones were synthesized and used as catalyst precursors for ethylene polymerization.
Abstract: On the basis of the strategy of promoting thermostability of α-diimine nickel catalyst by ligand backbone framework, a series of α-diimine nickel(II) complexes with bulky camphyl or diaryl-substituted backbones, [2,6-(R2)2C6H3−N═C(R1)−C(R1)═N−2,6-(R2)2C6H3]NiBr2 (1a, R1 = Ph, R2 = CH3; 2a, R1 = 4-methylphenyl, R2 = CH3; 3a, R1 = 4-fluorophenyl, R2 = CH3; 4a, R1 = camphyl, R2 = CH3; 4b, R1 = camphyl, R2 = i-Pr), were synthesized and used as catalyst precursors for ethylene polymerization. Crystallographic analysis revealed that the bulky camphyl backbone has a valid steric-effect on the nickel center by blocking the axial site for the metal center and suppressing the potential rotation of the CAr−N bond. Ethylene polymerizations catalyzed by these nickel α-diimine complexes activated by MAO were systematically investigated and the influences of the substituted backbones as well as reaction temperature on the catalytic activity, molecular weight and branching structure of the polymers were evaluated. It was...
219 citations
••
TL;DR: In this article, composite layers of modified amorphous nickel were prepared by simultaneous electrodeposition of Ni and TiO2 on a Cu substrate from a solution containing TiO 2 (anatase) particles suspended by stirring.
219 citations
••
TL;DR: In this paper, the carbon formation/gasification equilibrium was the same for the alloy catalysts as for monometallic nickel catalysts except at the highest copper concentration (80 at.% Cu).
219 citations