Formation and stability of reduced Ti Ox layers on anatase Ti O2(101 ) : Identification of a novel T i2O3 phase
Abstract
We use density functional theory (DFT) calculations to investigate structural models consisting of anatase Ti O2(101 ) slabs covered by reduced overlayers formed by (101) crystallographic shear planes (CSPs). Ab initio thermodynamics supports the stability of these structures under a wide range of experimental conditions. The overlayers are found to have T i2O3 stoichiometry with a crystal structure different from the known corundumlike T i2O3 (here denoted a α -T i2O3 ) phase. DFT calculations predict this new "csp -T i2O3 " phase to be energetically close to α -T i2O3 and to have also a similar band gap. These results suggest a possible role of the csp -T i2O3 phase in the properties of black Ti O2 , a promising photocatalytic material made of nanoparticles with a crystalline Ti O2 core and a highly reduced Ti Ox shell that is capable of absorbing the whole spectrum of visible light.
- Publication:
-
Physical Review Materials
- Pub Date:
- January 2018
- DOI:
- 10.1103/PhysRevMaterials.2.015801
- arXiv:
- arXiv:1712.05791
- Bibcode:
- 2018PhRvM...2a5801Z
- Keywords:
-
- Condensed Matter - Materials Science
- E-Print:
- Phys. Rev. Materials 2, 015801 (2018)