物理学报Issue(24)：1-8,8.DOI:10.7498/aps.63.243102
TiO2纳米管电子结构和光学性质的第一性原理研究∗
First-principles study of electronic structure and optical prop erties of TiO2 nanotub es
摘要
Abstract
Using first-principles calculations based on the density functional theory, we systematically study the geometry structure, electronic structure and optical properties of the small size (n, 0)-type TiO2 nanotubes (D <16 Å) derived from anatase. The calculation results indicate that the formation energy of each TiO2 unit decreases with the diameter increasing, and the nanotubes become more stable. At a diameter of about 14 Å, a configuration change occurs. Band structure analysis shows that electronic states of TiO2 nanotubes are localized, and the conductivity is better for nanotubes with small diameters (D <14 Å). According to the configuration change, TiO2 nanotubes shift from direct band gap to indirect band gap. And the band gap increases with diameter increasing, because π orbital overlap effect is greater than the quantum confinement effect. Owing to the competition between the two effects, the peaks of the dielectric function ε2(ω) will become redshifted or blueshifted. When its diameter is larger than 9 Å ((8, 0) tube), the optical absorption of TiO2 nanotubes will be significantly enhanced.关键词
TiO2纳米管/第一性原理/电子结构/光学性质Key words
TiO2 nanotubes/first-principles/electronic structure/optical properties引用本文复制引用
谢知,程文旦..TiO2纳米管电子结构和光学性质的第一性原理研究∗[J].物理学报,2014,(24):1-8,8.基金项目
福建省自然科学基金(批准号:2011J05121)和福建农林大学校青年教师基金(批准号:2010025)资助的课题.@@@@* Project supported by the Natural Science Foundation of Fujian Province, China (Grant No.2011J05121) and the Foundation for Young Teachers of Fujian Agriculture and Forestry University, China (Grant No.2010025) （批准号:2011J05121）
