CoFeRh alloys

• Published in: Electrochimica acta 2008, Vol.53 (5), p.2483-2493
• Main Authors: Tabakovic, Ibro, Qiu, Jiao-Ming, Riemer, Steve, Sun, Ming, Vas’ko, Vlad, Kief, Mark
• Format: Article
• Language: English
• Subjects: Electrodeposition of Rh and nonmagnetic CoFeRh; Foreign elements in Rh and CoFeRh films; Nucleation and growth
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2007.10.045

The electrochemical behavior of Rh(III) species in CoFe solution containing RhCl 3, NH 4Cl, H 3BO 3, CoSO 4, FeSO 4, saccharin, and NaLS (Na lauryl sulfate) has been investigated. The electrochemistry of Rh(III) species is influenced by each of the compounds present in CoFe plating solution, but especially by addition of saccharin and H 3BO 3 to the RhCl 3-NH 4Cl solution. The nucleation and growth of Rh on GC (glassy carbon), Ru, and Cu electrodes from NH 4Cl solution was studied using the potentiostatic current-transient methods. The results support a predominantly progressive nucleation of Rh on all three-electrode surfaces. The nucleation kinetic parameters ANo (steady state nucleation rate) and Ns (saturation nuclear number density) were found to vary with potential and are electrode-dependent in order: GC > Ru∼Cu. The electrodeposited Rh films obtained from NH 4Cl solution and nonmagnetic CoFeRh film obtained from CoFe solution were characterized in terms of the following properties: morphology, surface roughness, crystal structure and chemical composition. The origin of light elements found in Rh and CoFeRh films (O, Cl, S, C, N) was discussed.