Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode
Samo za registrovane korisnike
2005
Članak u časopisu (Objavljena verzija)
Metapodaci
Prikaz svih podataka o dokumentuApstrakt
The kinetics of methanol oxidation at PtRu catalyst was investigated on a membrane electrode assembly (MEA) in a cyclone flow cell. Catalyst characterisation was done by means of cyclic voltammetry and CO stripping. The influence of the flow rate (10-20 l/h), the methanol concentration (0.03-3 M) and the temperature (22-61 °C) was checked. The reaction order with respect to methanol was found to vary from zero (low potential, high concentrations) to close to unity (high potentials), where limiting currents are recorded. A model for the anodic oxidation of methanol, based on a bifunctional mechanism was presented, which includes methanol adsorption on the Pt sites, formation of OHads on the Ru sites and surface reaction between these adsorbed species. For Langmuir adsorption conditions it predicted reaction order, Tafel slopes and activation energies in qualitative agreement with the experimental observations. The kinetic parameters were determined by fitting the experimental curves. So...me modifications of the model were tested as well - Sips adsorption conditions on the Pt sites; Frumkin adsorption conditions; diffusion through the back diffusion layer and the Nafion membrane. No significant improvement has been achieved, although Frumkin conditions seem to describe better the anodic behaviour outside of the limiting current region. From these simulations it is difficult to decide whether the reaction between adsorbed methanol and OH ads depends on potential or not.
Ključne reči:
Cyclone flow cell / DMFC / Kinetics of methanol oxidation / Model / PtRu catalystIzvor:
Journal of Electroanalytical Chemistry, 2005, 580, 1, 105-121Izdavač:
- Elsevier
Finansiranje / projekti:
- Max Planck Society in Germany.
DOI: 10.1016/j.jelechem.2005.03.015
ISSN: 1572-6657
WoS: 000229512700013
Scopus: 2-s2.0-18444403463
Institucija/grupa
Tehnološko-metalurški fakultetTY - JOUR AU - Vidaković, Tanja AU - Christov, Mihai AU - Sundmacher, Kai PY - 2005 UR - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5483 AB - The kinetics of methanol oxidation at PtRu catalyst was investigated on a membrane electrode assembly (MEA) in a cyclone flow cell. Catalyst characterisation was done by means of cyclic voltammetry and CO stripping. The influence of the flow rate (10-20 l/h), the methanol concentration (0.03-3 M) and the temperature (22-61 °C) was checked. The reaction order with respect to methanol was found to vary from zero (low potential, high concentrations) to close to unity (high potentials), where limiting currents are recorded. A model for the anodic oxidation of methanol, based on a bifunctional mechanism was presented, which includes methanol adsorption on the Pt sites, formation of OHads on the Ru sites and surface reaction between these adsorbed species. For Langmuir adsorption conditions it predicted reaction order, Tafel slopes and activation energies in qualitative agreement with the experimental observations. The kinetic parameters were determined by fitting the experimental curves. Some modifications of the model were tested as well - Sips adsorption conditions on the Pt sites; Frumkin adsorption conditions; diffusion through the back diffusion layer and the Nafion membrane. No significant improvement has been achieved, although Frumkin conditions seem to describe better the anodic behaviour outside of the limiting current region. From these simulations it is difficult to decide whether the reaction between adsorbed methanol and OH ads depends on potential or not. PB - Elsevier T2 - Journal of Electroanalytical Chemistry T1 - Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode EP - 121 IS - 1 SP - 105 VL - 580 DO - 10.1016/j.jelechem.2005.03.015 ER -
@article{ author = "Vidaković, Tanja and Christov, Mihai and Sundmacher, Kai", year = "2005", abstract = "The kinetics of methanol oxidation at PtRu catalyst was investigated on a membrane electrode assembly (MEA) in a cyclone flow cell. Catalyst characterisation was done by means of cyclic voltammetry and CO stripping. The influence of the flow rate (10-20 l/h), the methanol concentration (0.03-3 M) and the temperature (22-61 °C) was checked. The reaction order with respect to methanol was found to vary from zero (low potential, high concentrations) to close to unity (high potentials), where limiting currents are recorded. A model for the anodic oxidation of methanol, based on a bifunctional mechanism was presented, which includes methanol adsorption on the Pt sites, formation of OHads on the Ru sites and surface reaction between these adsorbed species. For Langmuir adsorption conditions it predicted reaction order, Tafel slopes and activation energies in qualitative agreement with the experimental observations. The kinetic parameters were determined by fitting the experimental curves. Some modifications of the model were tested as well - Sips adsorption conditions on the Pt sites; Frumkin adsorption conditions; diffusion through the back diffusion layer and the Nafion membrane. No significant improvement has been achieved, although Frumkin conditions seem to describe better the anodic behaviour outside of the limiting current region. From these simulations it is difficult to decide whether the reaction between adsorbed methanol and OH ads depends on potential or not.", publisher = "Elsevier", journal = "Journal of Electroanalytical Chemistry", title = "Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode", pages = "121-105", number = "1", volume = "580", doi = "10.1016/j.jelechem.2005.03.015" }
Vidaković, T., Christov, M.,& Sundmacher, K.. (2005). Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode. in Journal of Electroanalytical Chemistry Elsevier., 580(1), 105-121. https://doi.org/10.1016/j.jelechem.2005.03.015
Vidaković T, Christov M, Sundmacher K. Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode. in Journal of Electroanalytical Chemistry. 2005;580(1):105-121. doi:10.1016/j.jelechem.2005.03.015 .
Vidaković, Tanja, Christov, Mihai, Sundmacher, Kai, "Rate expression for electrochemical oxidation of methanol on a direct methanol fuel cell anode" in Journal of Electroanalytical Chemistry, 580, no. 1 (2005):105-121, https://doi.org/10.1016/j.jelechem.2005.03.015 . .