Abstract
Nitrogen doping-induced changes in the electronic properties, defect formation, and surface structure of rutile(110) and anatase(101) single crystals were investigated. No band gap narrowing is observed, but N doping induces localized N states within the band gap just above the valence band. N is present in a N(III) valence state, which facilitates the formation of oxygen vacancies and Ti band gap states at elevated temperatures. The increased O vacancy formation triggers the reconstruction of the rutile (110) surface. This thermal instability may degrade the catalyst during applications.
- Received 25 July 2005
DOI:https://doi.org/10.1103/PhysRevLett.96.026103
©2006 American Physical Society