Electrodeposition of polypyrrole–titanate nanotube composites coatings and their corrosion resistance

✍ Scribed by P. Herrasti; A.N. Kulak; D.V. Bavykin; C. Ponce de Léon; J. Zekonyte; F.C. Walsh

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 699 KB
• Volume: 56
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/j.electacta.2010.09.094

✦ Synopsis

Polypyrrole (PPy) films (2 m) containing titanate nanotubes (TiNT) were deposited from 0.5 mol dm -3 pyrrole (Py) and 1 g dm -3 of TiNT in 0.1 mol dm -3 aqueous oxalic acid on 904 L stainless steel (SS) 0.1 mm thickness at 298 K. Electron microscopy showed that the nanotubes were adsorbed on the PPy surface and uniformly dispersed in the polymer matrix. The PPy/TiNT composite contained <10 wt.% titanates which showed an increase of 53% hardness compared with polypyrrole alone. The TiNT provide nucleation centres to catalyze the polymerization of pyrrole and can adsorb up to 240 mg g -1 of the monomer. The corrosion rates for SS, SS/PPy and SS/PPy/TiTN composites, evaluated by linear sweep voltammetry and open-circuit potential measurements in 3% w/v NaCl, were 1.61, 0.008 and 0.004 mg dm -2 day -1 , respectively, indicating that corrosion rates of stainless steel decreased by up to three orders of magnitude in the presence of the composite films.