Ni(Ⅱ) was reduced to Ni atom irreversibly by a one-step reaction in acetamide-urea-NaBr melt at 353K. The electron-transfer coefficient, and the diffusion coefficient, D0 were determined to be 0.21 and 1.15×10-8 cm2.s-1 on Pt electrode. Although the Ce(Ⅲ)and the Mg(Ⅱ)cannot be reduced to Ce and Mg alone, they can be inductively codeposited with Ni(Ⅱ)to obtain an amorphous Ce-Mg-Ni alloy film by potentiostatic electrolysis. The content of Ce in the alloy increase with the increasing of the molar ratio of Ce(Ⅲ)/Ni(Ⅱ) and reaches to the maximum of 49.70 wt%. The content of Mg in the alloy increase with the increasing of the cathode potential and the maximum was 4.558wt%.
Purpose
This paper aims to obtain rare earth magnesium alloy with good adhesion and corrosion resistance.
Design/methodology/approach
In 353 K oil bath, cyclic voltammetry was used to study the electrochemical behavior of Pr(III), Mg(II) and Ni(II) in choline chloride-urea ionic liquid. The constant potential method was adopted for electrodeposition of Pr-Mg-Ni ternary alloy films. The content of Pr in the Pr-Mg-Ni alloy films changes with respect to the deposition potential, deposition time and concentration ratio of Pr3+:Mg2+:Ni2+. Response surface methodology was applied to optimize the conditions for obtaining high-quality deposition films.
Findings
The results showed that the reaction of Ni(II) to Ni is irreversible; this result can be verified by Tafel polarization curve and chronocoulometry curve. Its transfer coefficient on the platinum electrode of 0.32 and diffusion coefficient is 1.0510−6 cm2.s−1. Mg(II) and Pr(III) cannot solely be reduced to their elemental form, but they can be induced via codeposition by Ni(II). The result shows that under a voltage of −1.00 V, the alloy coating with even structure is obtained when the concentration ratio of Pr3+:Mg2+:Ni2+ is 1:1:1 and the deposition time is 20 min. Scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and other analyses revealed that the alloy coating is amorphous. Polarization curves of the cathode are tested, which manifest the lowest corrosion current density, stating which has good corrosion performance in alkaline solution and NaCl solution; this can be attributed to its dense film structure and good combination with the substrate.
Originality/value
It provides some technology for the production of corrosion-resistant materials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.