CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Mechanism for Limiting Thickness of Thin Oxide Films on Aluminum

J. D. Baran ; Henrik Grönbeck (Institutionen för teknisk fysik, Kemisk fysik ; Kompetenscentrum katalys (KCK)) ; Anders Hellman (Institutionen för teknisk fysik, Kemisk fysik ; Kompetenscentrum katalys (KCK))
Physical Review Letters (0031-9007). Vol. 112 (2014), 14,
[Artikel, refereegranskad vetenskaplig]

A first-principles account of the observed limiting thickness of oxide films formed on aluminum during oxidizing conditions is presented. The results uncover enhanced bonding of oxygen to thin alumina films in contact with metallic aluminum that stems from charge transfer between a reconstructed oxide-metal interface and the adsorbed molecules. The first-principles results are compared with the traditional Cabrera-Mott (CM) model, which is a classical continuum model. Within the CM model, charged surface oxygen species and metal ions generate a (Mott) potential that drives oxidation. An apparent limiting thickness is observed as the oxidation rate decreases rapidly with film growth. The present results support experimental estimates of the Mott potential and film thicknesses. In contrast to the CM model, however, the calculations reveal a real limiting thickness that originates from a diminishing oxygen adsorption energy beyond a certain oxide film thickness.



Den här publikationen ingår i följande styrkeområden:

Läs mer om Chalmers styrkeområden  

Denna post skapades 2014-08-22. Senast ändrad 2015-03-30.
CPL Pubid: 201825

 

Läs direkt!

Lokal fulltext (fritt tillgänglig)

Länk till annan sajt (kan kräva inloggning)


Institutioner (Chalmers)

Institutionen för teknisk fysik, Kemisk fysik (1900-2015)
Kompetenscentrum katalys (KCK)

Ämnesområden

Energi
Materialvetenskap
Nanovetenskap och nanoteknik
Transport
Fysik

Chalmers infrastruktur

C3SE/SNIC (Chalmers Centre for Computational Science and Engineering)