writer：Yang, Weihu; Fang, Jiajia;Liu, Peng; Li, Junfeng; Cai, Kaiyong
keywords：TiO(2) nanotube; molecular dynamics; water permeation; theoretical structure
source：期刊
specific source：MOLECULAR PHYSICS 卷: 109 期: 6 页: 969-974 DOI: 10.1080/00268976.2011.561809 出版年: 2011
Issue time：2011年

 In this study, the theoretical structures of armchair (6, 6) and zigzag (12, 0) TiO(2) nanotubes (TiNTs) were constructed by rolling the (101) layer of an anatase TiO(2) crystal. The (101) layer was made using Materials Studio (MS) by cutting the cleave plane (101) of the anatase TiO(2) crystal. Based on these structures, the basic properties of TiO(2) nanotubes were investigated using MS. Molecular dynamics simulations were performed using the software NAMD to investigate the status and permeation of water through the TiO(2) nanotubes. Structure analysis shows that both the inner and outer walls of the structures were terminated with oxygen atoms. The thicknesses of single tube walls are smaller than that of a perfect triple layer (2.20 angstrom) in bulk anatase TiO(2). With regard to the bulk Ti-O bond length, the Ti-O bonds in the outer layer are elongated, and are shortened in the inner layer. Molecular dynamics simulation shows that the water molecules in the nanotubes move back and forth, as in one-dimensional Brownian motion. Moreover, the penetration properties of TiNTs are associated with their radii, with the TiNT with larger radii having better penetration properties. Thus, when used in drug delivery or filtration systems, armchair TiNT has a better effect than zigzag TiNT.