Post density functional theoretical studies of highly polar semiconductive Pb(Ti1-xNix)O3-x solid solutions: Effects of cation arrangement on band gap

被引：131

作者：

Gou, G. Y. ^{[1
]}

Bennett, J. W. ^{[2
]}

Takenaka, H. ^{[1
]}

Rappe, A. M. ^{[1
]}

机构：

[1] Univ Penn, Dept Chem, Makineni Theoret Labs, Philadelphia, PA 19104 USA

[2] Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA

来源：

PHYSICAL REVIEW B | 2011年 / 83卷 / 20期

关键词：

THIN-FILMS; POLARIZATION; INSULATORS; EXCHANGE;

D O I：

10.1103/PhysRevB.83.205115

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We use a combination of conventional density functional theory (DFT) and post-DFT methods, which include the local density approximation plus Hubbard U (LDA + U), PBE0, and self-consistent GW, to study the electronic properties of Ni-substituted PbTiO3 (Ni-PTO) solid solutions. We find that LDA calculations yield unreasonable band structures, especially for Ni-PTO solid solutions that contain an uninterrupted NiO2 layer. Accurate treatment of localized states in transition-metal oxides such as Ni-PTO requires post-DFT methods. B-site Ni/Ti cation ordering is also investigated. The B-site cation arrangement alters the bonding between Ni and O, and therefore strongly affects the band gap (E-g) of Ni-PTO. We predict thatNi-PTOsolid solutions should have a direct band gap in the visible light energy range, with polarization similar to the parent PbTiO3. This combination of properties makes Ni-PTO solid solutions promising candidate materials for solar energy conversion devices.

引用

页数：7