The dual pathway in action: decoupling parallel routes for CO2 production during the oscillatory electro-oxidation of methanol

Autor(es)

Nagao, Raphael ^[1] ; Cantane, Daniel A. ^[1] ; Lima, Fabio H. B. ^[1] ; Varela, Hamilton ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Chem Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[2] Ertl Ctr Electrochem & Catalysis, Kwangju 500712 - South Korea

• Tipo de documento: Artigo Científico
• Fonte: Physical Chemistry Chemical Physics; v. 14, n. 23, p. 8294-8298, 2012.
• Citações Web of Science: 31

Resumo

As in the case of most small organic molecules, the electro-oxidation of methanol to CO2 is believed to proceed through a so-called dual pathway mechanism. The direct pathway proceeds via reactive intermediates such as formaldehyde or formic acid, whereas the indirect pathway occurs in parallel, and proceeds via the formation of adsorbed carbon monoxide (COad). Despite the extensive literature on the electro-oxidation of methanol, no study to date distinguished the production of CO2 from direct and indirect pathways. Working under, far-from-equilibrium, oscillatory conditions, we were able to decouple, for the first time, the direct and indirect pathways that lead to CO2 during the oscillatory electro-oxidation of methanol on platinum. The CO2 production was followed by differential electrochemical mass spectrometry and the individual contributions of parallel pathways were identified by a combination of experiments and numerical simulations. We believe that our report opens some perspectives, particularly as a methodology to be used to identify the role played by surface modifiers in the relative weight of both pathways-a key issue to the effective development of catalysts for low temperature fuel cells. (AU)

• Processo FAPESP: 08/05156-0 - Eletrocatálise de oxidação de etanol em monocamadas de platina depositadas em nanopartículas do tipo core-shell
• Beneficiário: Fabio Henrique Barros de Lima
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/07629-6 - Eletrocatálise IV: aspectos fundamentais e aplicados dos processos eletrocatalíticos, bio-eletrocatálise e instabilidades cinéticas
• Beneficiário: Edson Antonio Ticianelli
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Temático
• Processo FAPESP: 09/11073-3 - Investigação do mecanismo de eletro-oxidação do etanol em nanopartículas metálicas.
• Beneficiário: Daniel Augusto Cantane
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 09/00153-6 - Auto-organização espaço-temporal em eletrocatálise
• Beneficiário: Raphael Nagao de Sousa
• Modalidade de apoio: Bolsas no Brasil - Doutorado