Zinc Anode for Direct Borohydride Fuel Cells

• Tipo: Artigo em Revista Científica Internacional
• Data: 2010

Autores

Sequeira, CAC (Autor) Outra

Revista

Título: Journal of the Electrochemical Society

Vol. 157 Nº 5

Páginas: B13-B19

ISSN: 0013-4651

Editora: Electrochemical Society, Inc.

Indexação

ISI Web of Knowledge - 54 Citações

Scopus - 63 Citações

Outras Informações

ID Authenticus: P-003-BS7

DOI: 10.1149/1.3247540

Abstract (EN): Zinc is evaluated as a negative electrode for the direct electrochemical oxidation of sodium borohydride (NaBH4). Open-circuit potential measurements, cyclic voltammetry, chronoamperometry, and chronopotentiometry are used to characterize the electrode behavior, namely, the oxidation reaction at the Zn/borohydride interface. Two consecutive oxidation steps are identified, and a possible working mechanism is proposed. A relatively low electrocatalytic activity of Zn for borohydride oxidation is indicated. A laboratory direct sodium borohydride/hydrogen peroxide (NaBH4/H2O2) fuel cell using a Zn anode is studied at room temperature. Cell voltages of 2.14 V and short-circuit currents of 1.05 A cm(-2) are reported but cell stability is limited to 6 h operation. Energy densities and maximum specific capacities of 2799 Wh kg(-1) and 1577 Ah kg(-1), respectively, are obtained. A power density of about 470 mW cm(-2) at a cell voltage of 1.10 V and a current density of 426 mA cm(-2) is reported but it cannot be sustained for appreciable operation times.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7