Journalartikel

Jahr der Veröffentlichung: 2011

Seiten: 12798-12807

Zeitschrift: Physical Chemistry Chemical Physics

Bandnummer: 13

Heftnummer: 28

ISSN: 1463-9076

eISSN: 1463-9084

DOI Link: https://doi.org/10.1039/c1cp20361d

Verlag: Royal Society of Chemistry

Abstract: 
Electrochemically induced oxygen spillover and diffusion in the Pt(O(2))vertical bar YSZ system is investigated in a combined experimental and theoretical study. The spreading of spillover oxygen is imaged by photoelectron emission microscopy (PEEM) on dense and epitaxial Pt(111) thin film electrodes prepared by pulsed laser deposition (PLD). Two different models are used to obtain surface diffusion coefficients from the experimental data, (i) an analytical solution of Fick's 2nd law of diffusion, and (ii) a numerical reaction-diffusion model that includes recombinative desorption of O(2) into the gas phase. The resulting diffusion coefficient has an activation energy of 50 kJ mol(-1) and a preexponential factor of 0.129 cm(2) s(-1) with an estimated uncertainty of +/- 20% for the activation energy and +/- 50% for the absolute value. The Fickian model slightly overpredicts diffusion coefficients due to the neglect of oxygen desorption. Experimental and theoretical results and limitations are discussed and compared to previous work.

Harvard-Zitierstil: Mutoro, E., Hellwig, C., Luerssen, B., Günther, S., Bessler, W. and Janek, J. (2011) Electrochemically induced oxygen spillover and diffusion on Pt(111): PEEM imaging and kinetic modelling, Physical Chemistry Chemical Physics, 13(28), pp. 12798-12807. https://doi.org/10.1039/c1cp20361d

APA-Zitierstil: Mutoro, E., Hellwig, C., Luerssen, B., Günther, S., Bessler, W., & Janek, J. (2011). Electrochemically induced oxygen spillover and diffusion on Pt(111): PEEM imaging and kinetic modelling. Physical Chemistry Chemical Physics. 13(28), 12798-12807. https://doi.org/10.1039/c1cp20361d