Oxygen reduction at a manganate electrocatalyst in KOH solutions

• Tipo: Artigo em Revista Científica Internacional
• Data: 2006

Autores

Sequeira, CAC (Autor) Outra; Baptista, W (Autor) Outra

Revista

Título: Journal of the Brazilian Chemical Society

Vol. 17

Páginas: 910-914

ISSN: 0103-5053

Editora: Sociedade Brasileira de Quimica

Indexação

ISI Web of Knowledge - 2 Citações

Scopus - 4 Citações

Outras Informações

ID Authenticus: P-004-HN0

DOI: 10.1590/s0103-50532006000500014

Abstract (EN): The electrocatalysis of the oxygen reduction reaction by lanthanum calcium manganate, (La0.5Ca0.5MnO3) (LCM) has been studied by cyclic voltammetry using the rotating ring-disc electrode technique (RRDE) in alkaline medium. From the ring-disc data and other kinetic parameters it has been assumed that the oxygen reduction occurs by dissociative chemisorption at low overpotentials. At higher overpotentials, the formation of hydrogen peroxide (HO2- in this case) has been observed on this electrocatalyst. The apparent exchange current density value for oxygen reduction on LCM has been found to be 5 x 10(-8) A cm(-2), while the corresponding Tafel slope is 0.115 V per decade. The possible reaction mechanism for electroreduction of oxygen on this oxide catalyst has been discussed.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 5