Electroreductive deposition of polymeric coatings having RuII redox centers on Pt, Pd and sintered Fe–(5–10)%Ni electrodes

Abstract

Pt, Pd and sintered Fe–(5–10)%Ni electrodes were coated by reductive electrodeposition of electrochemically generatedtrans-[RuCl₂(vpy)₄ ]-based films (vpy=4-vinylpyridine). The complex trans-[RuCl₂(vpy)₄ ] was synthesized from a ruthenium blue solution and characterized by various techniques including electronic spectroscopy (446 nm), FTIR, ¹H and ¹³C NMR elemental analysis and cyclic voltammetry (E_1/2=–103.5 mV vs. Ag–Ag⁺). The results obtained confirmed the proposed structure of the monomer. Electrochemical studies carried out on films generated by either a potentiostatic or a galvanostatic approach revealed that the redox properties of poly-trans-[RuCl₂(vpy)₄ ] were similar to those of the monomer in solution. The morphology of the films was investigated by scanning electron microscopy (SEM). Microprobe X-ray dispersive energy analysis (EDS) was also performed on the polymer surface. The feasibility of film formation on Fe–5%Ni and Fe–10%Ni sintered electrodes has been demonstrated.