Borohydride electrooxidation on Au and Pt electrodes

Author(s)

Lima, Fabio H. B. ; Pasqualeti, Anielli M. ; Concha, M. Belen Molina ; Chatenet, Marian ; Ticianelli, Edson A.

• Document type: Journal article
• Source: Electrochimica Acta; v. 84, p. 11-pg., 2012-12-01.

Abstract

Direct borohydride fuel cells (DBFCs) are attractive energy generators for powering portable electronic devices, mainly due to their high energy density and number of electrons per borohydride ion. However, the lack of a highly efficient electrocatalyst for the borohydride oxidation reaction limits the performance of these devices. The most commonly studied electrocatalysts for this reaction are composed of gold and platinum. Nevertheless, for these metals, the borohydride electrooxidation reaction mechanism (BOR) is not completely understood, and the total oxidation reaction, involving eight electrons per BH4- species, competes with parallel reactions, with a lower number of exchanged electrons and/or with heterogeneous chemical hydrolysis. Considering the above-mentioned issues, this work presents recent advances in the knowledge of the BOR pathways on polycrystalline (bulk) Au and Pt electrocatalysts. It presents the studies of the BOR reaction on Au and Pt electrodes using in situ Fourier Transform Infrared Spectroscopy (FUR), and on-line Differential Electrochemical Mass Spectrometry (DEMS). The spectroscopic and spectrometric data provided physical evidence of intermediate species and the formation of H-2 in the course of the BOR as a function of the electrode potential. These results enabled to advance in the knowledge about the BOR pathways on Au and Pt electrocatalysts. (C) 2012 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 09/07629-6 - Electrocatalysis IV: fundamental and applied aspects of electrocatalytic processes, bio-electrocatalysis and kinetic instabilities
• Grantee: Edson Antonio Ticianelli
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Thematic Grants
• FAPESP's process: 11/03672-4 - Investigation of the catalytic activity of nanostructured electrocatalysts for BH4- ions electrooxidation in alkaline media
• Grantee: Aniélli Martini Pasqualeti
• Support Opportunities: Scholarships in Brazil - Master