First-principles study on anatase TiO2(101) surface adsorption of NO |
| |
引用本文: | 冯庆,岳远霞,王渭华,朱洪强. First-principles study on anatase TiO2(101) surface adsorption of NO[J]. 中国物理 B, 2014, 0(4): 215-222 |
| |
作者姓名: | 冯庆 岳远霞 王渭华 朱洪强 |
| |
作者单位: | [1]College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China [2]Chongqing Key Laboratory on Optoelectronic Functional Materials, Chongqing 401331, China |
| |
基金项目: | Project supported by the National Natural Science Foundation of China(Grant Nos.61106129 and 61274128) |
| |
摘 要: | In this paper, the stable structure and the electronic and optical properties of nitric oxide (NO) adsorption on the anatase TiO2 (101) surface are studied using the plane-wave ultrasoft pseudopotential method, which is based on the density functional theory. NO adsorption on the surface is weak when the outermost layer terminates on twofold coordinated oxygen atoms, but it is remarkably enhanced on the surface containing O vacancy defects. The higher the concentration of oxygen vacancy defects, the stronger the adsorption is. The adsorption energies are 3.4528 eV (N end adsorption), 2.6770 eV (O end adsorption), and 4.1437 eV (horizontal adsorption). The adsorption process is exothermic, resulting in a more stable adsorption structure. Furthermore, O vacancy defects on the TiO2 (101) surface significantly contribute to the absorption of visible light in a relatively low-energy region. A new absorption peak in the low-energy region, corresponding to an energy of 0.9 eV, is observed. However, the TiO2 (101) surface structure exhibits weak absorption in the low-energy region of visible light after NO adsorption.
|
关 键 词: | 表面结构 TiO2 一氧化氮 吸附能 锐钛矿型 第一性原理 密度泛函理论 空位缺陷 |
First-principles study on anatase TiO_2 (101) surface adsorption of NO |
| |
Abstract: | In this paper, the stable structure and the electronic and optical properties of nitric oxide(NO) adsorption on the anatase TiO2(101) surface are studied using the plane-wave ultrasoft pseudopotential method, which is based on the density functional theory. NO adsorption on the surface is weak when the outermost layer terminates on twofold coordinated oxygen atoms, but it is remarkably enhanced on the surface containing O vacancy defects. The higher the concentration of oxygen vacancy defects, the stronger the adsorption is. The adsorption energies are 3.4528 eV(N end adsorption), 2.6770 eV(O end adsorption), and 4.1437 eV(horizontal adsorption). The adsorption process is exothermic, resulting in a more stable adsorption structure. Furthermore, O vacancy defects on the TiO2(101) surface significantly contribute to the absorption of visible light in a relatively low-energy region. A new absorption peak in the low-energy region, corresponding to an energy of 0.9 eV, is observed. However, the TiO2(101) surface structure exhibits weak absorption in the low-energy region of visible light after NO adsorption. |
| |
Keywords: | anatase TiO() surface first-principles density functional theory electronic structures |
本文献已被 CNKI 维普 等数据库收录! |
|