Electrocatalysis and transport effects on nanostructured Pt/GC electrodes
2010 (English)In: J ELECTROANAL CHEM, ISSN 1572-6657, Vol. 644, no 2, 90-102 p.Article in journal (Refereed) Published
The role and contribution of transport processes in electrocatalytic reactions was investigated in model studies of the oxidation of CO (single-product reaction) and formaldehyde (dual-product reaction), using nanostructured Pt/glassy carbon electrodes with variable Pt loading and defined reactant transport conditions. Nanostructured electrodes with monodispersed, uniformly distributed Pt nanostructures (100-140 nm diameter) supported on planar glassy carbon (GC) electrodes with different densities were prepared by Colloidal Lithography (CL) or Hole-Mask Colloidal Lithography (HCL). Transport effects were evaluated by varying the density of the nanostructures and the electrolyte flow. The resulting changes in the transport limited reaction current (CO oxidation - transition from planar to spherical diffusion with decreasing Pt nanostructure density) and in the distribution of the reaction products HCOOH and CO2 (HCHO oxidation), which is probed by differential electrochemical mass spectrometry (DEMS), are discussed focusing on transport effects. The increasing amount of CO2 with decreasing space velocity (higher nanostructure density, lower electrolyte flow) is explained by increasing re-adsorption and further reaction of desorbing reaction intermediates. (C) 2009 Elsevier B.V. All rights reserved.
Place, publisher, year, edition, pages
2010. Vol. 644, no 2, 90-102 p.
Model catalyst, Nanostructuring, Colloidal Lithography, Hole-Mask Colloidal Lithography, Electrocatalysis, CO oxidation, Formaldehyde oxidation, Transport effects
IdentifiersURN: urn:nbn:se:kth:diva-27264DOI: 10.1016/j.jelechem.2009.04.034ISI: 000279100400002OAI: oai:DiVA.org:kth-27264DiVA: diva2:378761
QC 201012162010-12-162010-12-092010-12-16Bibliographically approved