Defect complexes in Li-doped MgO

N. A. Richter, F. Stavale, S. V. Levchenko, N. Nilius, H. J. Freund, M. Scheffler

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)

Abstract

Magnesium oxide (MgO) is used in a variety of industrial applications due to its low cost and structural stability. In heterogeneous catalysis, MgO and Li-doped MgO have been studied as catalysts for the oxidative coupling of methane. In this work, we analyze the structure and stability of defect complexes comprising Li dopants and oxygen vacancies in MgO, combining scanning tunneling microscopy, photon-emission experiments, and density-functional theory computations. The experimental results strongly indicate that after annealing Li-doped MgO to temperatures of 600 K and higher, Li evaporates from the surface, but Li defects, such as substitutional defects, interstitials, or defect complexes comprising Li remain in the bulk. Our calculations show that bulk defect complexes containing F2+ color centers, that have donated their two electrons to two adjacent Li defects, are the most stable configurations at realistic pressure and temperature conditions.

Original languageEnglish
Article number195305
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume91
Issue number19
DOIs
Publication statusPublished - 7 May 2015
Externally publishedYes

Fingerprint

Dive into the research topics of 'Defect complexes in Li-doped MgO'. Together they form a unique fingerprint.

Cite this