Electrocatalytic Activity of Pt Nanoparticles on Karst-Rock Shaped Ni Thin Films toward Methanol and Ethanol Oxidation in Alkaline Solutions

Abstract

We prepared Ni thin films with a karst-rock topography on the Si substrate and used the thin film as the electrocatalyst support for the study of methanol and ethanol oxidation in alkaline media. Well-dispersed Pt nanoparticles were pulse-electrodeposited on the rugged Ni thin film, which provided a very large surface for the Pt loading. The cyclic voltammertry (CV) showed that the Pt/Ni electrode had a high electrocatalytic activity toward methanol oxidation compared with blanket Pt. Nanosized Pt particles electrodeposited on the rugged surface of the Ni thin film provide a large amount of electrocatalytic sites for methanol oxidation. Hydroxyl surface groups bound on the Ni karst-rock nanostructures in the alkaline solution may greatly enhance CO electro-oxidation in terms of the bifunctional mechanism. The study demonstrates that the karst-rock shaped Ni thin film is a potential candidate as the Pt electrocatalyst support for direct methanol alkali fuel cells.