On the Limit of Frequency of Electrochemical Oscillators and Its Relationship to Kinetic Parameters

Autor(es)

Kiss, Istvan Z. ^[1] ; Sitta, Elton ^[2] ; Varela, Hamilton ^{[2, 3]}

Afiliação do(s) autor(es)

^[1] St Louis Univ, Dept Chem, St Louis, MO 63103 - USA

^[2] Univ Sao Paulo, Inst Chem Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[3] GIST, Ertl Ctr Electrochem & Catalysis, Kwangju 500712 - South Korea

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry C; v. 116, n. 17, p. 9561-9567, MAY 3 2012.
• Citações Web of Science: 7

Resumo

The class of electrochemical oscillators characterized by a partially hidden negative differential resistance in an N-shaped current potential curve encompasses a myriad of experimental examples. We present a comprehensive methodological analysis of the oscillation frequency of this class of systems and discuss its dependence on electrical and kinetic parameters. The analysis is developed from a skeleton ordinary differential equation model, and an equation for the oscillation frequency is obtained. Simulations are carried out for a model system, namely, the nickel electrodissolution, and the numerical results are confirmed by experimental data on this system. In addition, the treatment is further applied to the electro-oxidation of ethylene glycol where unusually large oscillation frequencies have been reported. Despite the distinct chemistry underlying the oscillatory dynamics of these systems, a very good agreement between experiments and theoretical predictions is observed. The application of the developed theory is suggested as an important step for primary kinetic characterization. (AU)

• 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