SwePub
Sök i LIBRIS databas

  Extended search

id:"swepub:oai:DiVA.org:kth-227568"
 

Search: id:"swepub:oai:DiVA.org:kth-227568" > First stages of oxi...

  • 1 of 1
  • Previous record
  • Next record
  •    To hitlist
  • Lousada, Claudio M.KTH,Materialvetenskap (author)

First stages of oxide growth on Al(1 1 0) and core-level shifts from density functional theory calculations

  • Article/chapterEnglish2018

Publisher, publication year, extent ...

  • Elsevier,2018
  • printrdacarrier

Numbers

  • LIBRIS-ID:oai:DiVA.org:kth-227568
  • https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-227568URI
  • https://doi.org/10.1016/j.apsusc.2018.01.246DOI

Supplementary language notes

  • Language:English
  • Summary in:English

Part of subdatabase

Classification

  • Subject category:ref swepub-contenttype
  • Subject category:art swepub-publicationtype

Notes

  • QC 20180517
  • The formation of islands of O-atoms is the dominant mode of growth of the oxide in the first stages of oxidation of Al(1 1 1). It is however unknown if a similar mechanism exists for other low index surfaces of Al. We performed a density functional theory (DFT) and ab initio molecular dynamics investigation of the first stages of the oxidation of Al(1 1 0) using two distinct models: a homogeneous surface disposition of O-atoms; and a model where the O-atoms are close-spaced forming clusters or islands. We investigated the surface reactions with oxygen up to a coverage of 2 ML and found that for both models the adsorption energy per dissociating O2(g) becomes more negative with increasing coverage. Our results show that for coverages up to 1.25 ML the oxide forms clusters or islands while for coverages higher than 1.5 ML the oxide covers the surface homogeneously. This is because the O-atoms bind preferably to neighboring sites even at the minimum coverage. With increasing coverage, the clusters of O start to form stripes along the [1 1¯ 0] direction. The work function (ϕ) of the surface decreases when going from bare Al(1 1 0) to up to 1 ML coverage of O-atoms, but for coverages of 1.25 ML and higher, ϕ increases. The Al 2p surface core level shifts (SCLS) shift towards higher binding energies with increasing surface coverage of O-atoms and start to approach the values of Al 2p in Al2O3 already at a coverage of 2ML. A relation between the SCLS and the coordination number of Al to O-atoms was made. The Al 2p SCLS increases with increasing coordination to O-atoms, for single, twofold and three-fourfold coordinated cations. For the O-atoms that terminate the surface at the short-bridge sites, the SCLS of O 1s, is largely affected by the proximity to other O-atoms. These results demonstrate that the cooperative effects between surface bound O-atoms have important roles in the mechanism of growth of the oxide at Al(1 1 0), and similarly to what happens for Al(1 1 1), the initial oxidation of Al(1 1 0) proceeds via the formation of islands of O-atoms.

Subject headings and genre

Added entries (persons, corporate bodies, meetings, titles ...)

  • Korzhavyi, Pavel A.,1966-KTH,Materialvetenskap(Swepub:kth)u17nfa0i (author)
  • KTHMaterialvetenskap (creator_code:org_t)

Related titles

  • In:Applied Surface Science: Elsevier441, s. 174-1860169-43321873-5584

Internet link

Find in a library

To the university's database

  • 1 of 1
  • Previous record
  • Next record
  •    To hitlist

Find more in SwePub

By the author/editor
Lousada, Claudio ...
Korzhavyi, Pavel ...
About the subject
ENGINEERING AND TECHNOLOGY
ENGINEERING AND ...
and Materials Engine ...
Articles in the publication
Applied Surface ...
By the university
Royal Institute of Technology

Search outside SwePub

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view