First-principles study of the atomic structures,electronic properties,and surface stability of BaTiO3 (001) and (011) surfaces |
| |
| Authors: | Mi Zhong Wei Zeng Fu-Sheng Liu Bin Tang Qi-Jun Liu |
| |
| Affiliation: | 1. School of Physical Science and Technology, Southwest Jiaotong University, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Chengdu, People's Republic of China;2. Teaching and Research Group of Chemistry, College of Medical Technology, Chengdu University of Traditional Chinese Medicine, Chengdu, People's Republic of China;3. School of Physical Science and Technology, Southwest Jiaotong University, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Chengdu, People's Republic of China Bond and Band Engineering Group, Sichuan Provincial Key Laboratory (for Universities) of High Pressure Science and Technology, Southwest Jiaotong University, Chengdu, People's Republic of China;4. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, People's Republic of China |
| |
| Abstract: | The atomic structures, electronic properties, and surface stability of (001) and (011) surfaces of BaTiO3 are studied by first-principles calculations. Four differently terminated BaTiO3 surfaces are considered in this study, including (001)-BaO, (001)-TiO2, (011)-BaTiO, and (011)-O2 terminations. The relaxations and rumplings are calculated and discussed, finding that the first layer relaxes inwards, while the second layer relaxes outwards for (001) and (110) surfaces. The data obtained for electronic properties show that O2p states in (001)-BaO/(001)-TiO2 termination shift to the lower/higher energy region, leading to a wide/narrow band gap. And the new produced surface states are observed in (011) surface terminations, which is mainly attributed to the supplied electrons from outermost surface atoms, even O atoms are oxidized. Furthermore, the (001) surface of BaTiO3 is found to be more stable than the (011) surface according to the predicted surface energy which is 0.86 and 2.92 J/m2 for (001) and (011) surfaces, respectively. Of which, BaO termination is predicted to be more likely to cleavage from the (001) direction than the TiO2 termination is. |
| |
| Keywords: | BaTiO3 electronic structures first-principles calculations surface energy surface relaxation |
|
|
