Iodide surface coverage and its effect on the rate constants during hydrogen charging and permeation in iron

Autor:	Konrad G. Weil, F.M. Al-Faqeer, Howard W. Pickering
Rok vydání:	2003
Předmět:	chemistry.chemical_classification Hydrogen Chemistry General Chemical Engineering Iodide Inorganic chemistry Analytical chemistry chemistry.chemical_element Sulfuric acid Electrolyte Quartz crystal microbalance Reaction inhibitor Electrochemistry chemistry.chemical_compound Reaction rate constant
Zdroj:	Electrochimica Acta. 48:3565-3572
ISSN:	0013-4686
DOI:	10.1016/s0013-4686(03)00425-0
Popis:	This paper demonstrates the use of the new Iyer/Pickering/Zamanzadeh/Al-Faqeer (IPZA) analysis to determine the effect of the iodide surface coverage (θI−) on the hydrogen surface coverage (θH) and the rate constants of the hydrogen evolution reaction (HER) and hydrogen absorption reaction (HAR). Iodide ions have an inhibiting effect on the HER but they enhance the HAR. The IPZA analysis was used to determine θI− in addition to the usual parameters: hydrogen discharge (k1) and recombination (k2) rate constants, hydrogen kinetic-diffusion constant (k) and θH. Inclusion of the iodide coverage is important as shown by a comparison with literature values that were obtained using the original IPZ analysis, which does not include the θI− parameter. The θI− values from the IPZA analysis were within reasonable agreement with θI− values measured using the electrochemical quartz crystal microbalance (EQCM) and θI− values calculated from the measured corrosion current densities before and after adding iodide to the electrolyte.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::7b94a46c47bfb0ead66290e67e4de036 https://doi.org/10.1016/s0013-4686(03)00425-0 Zobrazit plný text záznamu Full Text from ScienceDirect