物理化学学报 >> 2011, Vol. 27 >> Issue (10): 2311-2318.doi: 10.3866/PKU.WHXB20110920

理论与计算化学 上一篇    下一篇

CO分子在不同类型Al2O3表面的吸附构型和电子结构

臧丽莉1, 胡建明2, 孙玉1, 金华1, 朱佳1, 李奕1,3, 黄昕1, 章永凡1,3   

  1. 1. 福州大学化学化工学院, 福州 350108;
    2. 武警福州指挥学院, 福州 350002;
    3. 福建省光催化重点实验室-省部共建国家重点实验室培育基地, 福州 350002
  • 收稿日期:2011-04-08 修回日期:2011-06-03 发布日期:2011-09-27
  • 通讯作者: 章永凡 E-mail:zhangyf@fzu.edu.cn
  • 基金资助:

    国家自然科学基金(20773024, 21073035, 21071031), 福建省自然科学基金(2008J0151)和福州大学科技发展基金(2008-XQ-07)资助

Geometry and Electronic Structure of the Adsorption of CO Molecules on Different Al2O3 Surfaces

ZANG Li-Li1, HU Jian-Ming2, SUN Yu1, JIN Hua1, ZHU Jia1, LI Yi1,3, HUANG Xin1, ZHANG Yong-Fan1,3   

  1. 1. College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, P. R. China;
    2. Fuzhou Command Academy, the Chinese People's Armed Police Force, Fuzhou 350002, P. R. China;
    3. State Key Laboratory Breeding Base of Photocatalysis, Fuzhou 350002, P. R. China
  • Received:2011-04-08 Revised:2011-06-03 Published:2011-09-27
  • Contact: ZHANG Yong-Fan E-mail:zhangyf@fzu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20773024, 21073035, 21071031), Natural Science Foundation of Fujian Province, China (2008J0151) and Science and Technology Development Fund of Fuzhou University, China (2008-XQ-07).

摘要: 采用基于赝势平面波基组的密度泛函理论方法对CO 分子在α-Al2O3(0001)以及γ-Al2O3 的(100)、(110C)、(110D)表面上的吸附构型和电子结构进行系统研究. 计算结果表明, CO倾向于选取C端吸附在表层Al原子上, 并主要通过其5σ轨道与表面发生作用, 吸附后部分电子从CO转移到底物, 导致各Al2O3表面功函均发生不同程度的下降. 与气相相比, 吸附后CO分子的C―O伸缩振动频率均发生蓝移. 通过对比CO在各表面上的吸附情况, 可以看出CO可作为检测Al2O3不同类型表面活性中心的有效探针分子.

关键词: Al2O3表面, CO分子, 吸附, 电子结构

Abstract: Periodic density functional theory calculations using pseudopotential plane-waves were performed systematically to investigate the surface relaxation of different Al2O3 surfaces including α-Al2O3 (0001) and γ-Al2O3 (110), (110C), and (110D) surfaces, as well as the adsorption of CO molecules on these surfaces. Our calculated results indicate that the CO molecules tend to adsorb perpendicularly on the Al atoms at the surface through carbon atoms and interactions were observed between the CO 5σ state and the substrate. After adsorption, some electrons transferred from the CO molecules to the surface and accordingly the surface work functions of the different Al2O3 surfaces decreased. The adsorption results in small perturbations of the C ― O bond length and the corresponding C ― O stretching frequency was blue-shifted in all the adsorption structures. By examining the results of the CO adsorption on the different surfaces, it is clear that CO can be used as an effective probe molecule to distinguish the active adsorption sites on the different Al2O3 surfaces.

Key words: Al2O3 surface, CO molecule, Adsorption, Electronic structure

MSC2000: 

  • O641