Easy Preparation of Electrode Surfaces with Dispersed Size-Controlled Au Nanoparticles by Electrodeposited PPI-Dendrimers as Templates. Issue 6 (1st January 2017)

• Record Type: Journal Article
• Authors: Villena, Carlos; Losada, José; Alonso, Beatriz; Casado, Carmen M.; Armada, M. Pilar García
• Is Part Of: Journal of the Electrochemical Society. Volume 164:Issue 6(2017)
• Page Start: H396
• Page End: H406
• Publication Date: 2017-01-01
• Subjects: Dendrimer-templates -- modified electrodes -- nanostructures surfaces -- size-controlled Au nanoparticles; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.1611706jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The main target of this work is the preparation of nanostructurated surfaces with size-controlled gold nanoparticles to obtain effective electrocatalytic surfaces. In this paper, we show that dispersed Au nanoparticles (AuNPs) having diameters of less than 3 nm can be synthesized in situ with aminoferrocenyl- and amidoferrocenyl-poly(propyleneimine) (PPI) dendrimers previously electrodeposited onto electrode surfaces. Dendrimers of first, third and fifth generation have been studied and good dispersed non aggregated nanoparticles were obtained in all the cases. In a similar way than in homogeneous media, inter-dendrimer Au nanoparticles have been obtained when first or third generation dendrimer modified electrodes were used, while smaller nanoparticles were obtained with fifth generation dendrimer, indicating that intra-dendrimer Au nanoparticles have been synthesized. The AuNPs were obtained from a HAuCl4 solution after chemical reduction with NaBH4 . The formation of AuNPs was followed by UV-Vis spectroscopy; electrochemistry and ultra-high resolution scan electron microscopy (HRSEM). The obtained electrodes have been successfully used for the tetraelectronic oxygen reduction reaction (ORR) with a low onset potential (0.00 V vs. SCE), high kinetic current densities and also high heterogeneous electron transfer rate constants.