Elucidation of temperature-programmed desorption of high-coverage hydrogen on Pt(211), Pt(221), Pt(533) and Pt(553) based on density functional theory calculations

Autor: Marc T. M. Koper, José A. Garrido Torres, Egill Skúlason, Ludo B. F. Juurlink, Manuel J. Kolb, Hannes Jónsson, Cansin Badan, Anna L. Garden
Přispěvatelé: Iðnaðarverkfræði-, vélaverkfræði- og tölvunarfræðideild (HÍ), Faculty of Industrial Eng., Mechanical Eng. and Computer Science (UI), Verkfræði- og náttúruvísindasvið (HÍ), School of Engineering and Natural Sciences (UI), Háskóli Íslands, University of Iceland
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Physical Chemistry Chemical Physics, 21(31), 17142-17151
Physical Chemistry Chemical Physics
Popis: Publisher's version (útgefin grein)
In this work we compute high-coverage hydrogen adsorption energies and geometries on the stepped platinum surfaces Pt(211) and Pt(533) which contain a (100)-step type and the Pt(221) and Pt(553) surface with a (111) step edge. We discuss these results in relation to ultra-high-vacuum temperature programmed desorption (TPD) data to elucidate the origin of the desorption features. Our results indicated that on surfaces with a (100)-step type, two distinct ranges of adsorption energy for the step and terrace are observed, which mirrors the TPD spectra for which we find a clear separation of the desorption peaks. For the (111) step type, the TPD spectra show much less separation of the step and terrace features, which we assign to the low individual adsorption energies for H atoms on this step edge. From our results we obtain a much clearer understanding of the surface-hydrogen bonding at high coverages and the origin of the different TPD features present for the two step types studied.
We gratefully acknowledge financial support from the Netherlands Organization for Scientific Research (NWO) as a TOP grant awarded to LBFJ and MTMK. This work was sponsored also by the NWO Exacte Wetenschappen, EW (NWO Physical Sciences Division) for the use of supercomputer facilities, with financial support from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (Netherlands Organisation for Scientific Research, NWO). Furthermore, we would like to thank the Nordic High Performance Computing Center (NHPC) and the New Zealand eScience Infrastructure (NeSi), funded jointly by NeSI’s collaborator institutions and through the Ministry of Business, Innovation and Employment’s research infrastructure programme. JAGT acknowledges the support of the U.S. Department of Energy, Chemical Sciences, Geosciences, and Biosciences (CSGB) Division of the Office of Basic Energy Sciences, via Grant DE-AC02-76SF00515 to the SUNCAT Center for Interface Science and Catalysis.
Databáze: OpenAIRE