MSINDO quantum chemical modeling study of water molecule adsorption at nano-sized anatase TiO2 surfaces

被引:21
作者
Wahab, Hilal S. [1 ]
Bredow, Thomas [2 ]
Aliwi, Salah M. [3 ]
机构
[1] Univ Technol Baghdad, Sch Appl Sci, Baghdad, Iraq
[2] Univ Bonn, Inst Phys & Theoret Chem, D-5300 Bonn, Germany
[3] Minst Higher Educ & Sci Res, Directorate Scholarships & Cultural Relat, Baghdad, Iraq
关键词
Water; Adsorption; Titanium oxide; Free clusters; Anatase; Semiempirical method;
D O I
10.1016/j.chemphys.2008.09.005
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In this work, We Studied the adsorption of water molecule onto the (1 0 0), (0 1 0) and (0 0 1) surfaces of nano-sized anatase TiO2 with semiempirical SCF MO method, MSINDO. The anatase TiO2 particles are modeled with free clusters (TiO2)(n), where n = 20-80. Whereas, the Surfaces have been modeled with two saturated clusters, Ti21O58H32 and Ti36O90H36. The Surface lattice fivefold coordinated titanium atoms (Ti-5C), which represent the Lewis acid sites, are selected as adsorption centers. We also investigated the effect of TiO2 cluster size oil the computed band gap energy. Results reveal that the electronic properties of a cluster in the lowest excited state differ from that of the ground state. Furthermore, the MSINDO band gap energies of 3.68-3.77 eV for the anatase TiO2 are in a fair accordance with other literature data. In agreement with other computational and experimental Studies, the dissociated form of water molecule adsorption oil anatase TiO2 Surfaces is always more stabilized than the molecular form. (C) 2008 Elsevier B.V. All rights reserved.
引用
收藏
页码:50 / 57
页数:8
相关论文
共 57 条
[1]  
Ahlswede B, 1999, J COMPUT CHEM, V20, P572, DOI 10.1002/(SICI)1096-987X(19990430)20:6<572::AID-JCC2>3.0.CO
[2]  
2-1
[3]  
Ahlswede B, 1999, J COMPUT CHEM, V20, P563, DOI 10.1002/(SICI)1096-987X(19990430)20:6<563::AID-JCC1>3.0.CO
[4]  
2-2
[5]  
Ajmera AA, 2002, CHEM ENG TECHNOL, V25, P173, DOI 10.1002/1521-4125(200202)25:2<173::AID-CEAT173>3.0.CO
[6]  
2-C
[7]   Reductive dechlorination of 1,1,2,2-tetrachloroethane [J].
Arnold, WA ;
Winget, P ;
Cramer, CJ .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2002, 36 (16) :3536-3541
[8]   Electronic and optical properties of anatase TiO2 [J].
Asahi, R ;
Taga, Y ;
Mannstadt, W ;
Freeman, AJ .
PHYSICAL REVIEW B, 2000, 61 (11) :7459-7465
[9]   ELECTRON-PARAMAGNETIC-RES STUDY OF TRAP-CENTERS PRODUCED ON TIO2 PARTICLES DURING WATER PHOTOLYSIS [J].
AVUDAITHAI, M ;
KUTTY, TRN .
MATERIALS RESEARCH BULLETIN, 1988, 23 (11) :1675-1683
[10]   PREPARATION AND CHARACTERIZATION OF QUANTUM SIZE ZINC-OXIDE - A DETAILED SPECTROSCOPIC STUDY [J].
BAHNEMANN, DW ;
KORMANN, C ;
HOFFMANN, MR .
JOURNAL OF PHYSICAL CHEMISTRY, 1987, 91 (14) :3789-3798