| Texto completo | |
| Autor(es): |
Calderon-Cardenas, Alfredo
;
Paredes-Salazar, Enrique A.
;
Mujica-Martinez, Cesar A.
;
Nagao, Raphael
;
Varela, Hamilton
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Physical Chemistry C; v. 124, n. 44, p. 12-pg., 2020-11-05. |
| Resumo | |
In this work, the effect of temperature on the electro-oxidation of formic acid on platinum was modeled and numerically investigated. Numerical simulations were carried out using an electrokinetic model recently validated through voltammetric and galvanostatic experiments. We show that the intrinsic electrocatalytic activity of the working electrode for the overall electrochemical reaction can hardly be interpreted from the apparent activation energy due to the complexity of the reaction scheme. A detailed analysis is possible through the estimation of the activation energies determined from the individual rate coefficients. By doing so, we observed that the direct pathway, with an activation energy of 91 kJ mol(-1) at 0.40 V and 72 kJ mol(-1) at 0.80 V, is the energetically easiest pathway for the formation of CO2 in the proposed reaction scheme. Regarding the self-organized potential oscillations under the galvanostatic regime, our model was able to reproduce experimentally observed results including the phenomena of temperature compensation and overcompensation. Importantly, we have introduced a formalism to classify the elementary steps that contribute to the increase and decrease of the oscillatory frequency in electrochemical systems. Our results shed light on the understanding of the temperature dependence of complex electrocatalytic reactions, and the developed methodology was proven to be robust and of general applicability. (AU) | |
| Processo FAPESP: | 16/01817-9 - Desenho e controle de padrões eletroquímicos auto-organizados |
| Beneficiário: | Raphael Nagao de Sousa |
| Modalidade de apoio: | Auxílio à Pesquisa - Jovens Pesquisadores |
| Processo FAPESP: | 17/11986-5 - Geração e Armazenamento de Novas Energias: trazendo desenvolvimento tecnológico para o país |
| Beneficiário: | Ana Flávia Nogueira |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia |
| Processo FAPESP: | 13/16930-7 - Eletrocatálise V: processos eletrocatalíticos de interconversão entre as energias química e elétrica |
| Beneficiário: | Edson Antonio Ticianelli |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |