科研之友
微信
新浪微博
Facebook
分享链接
摘要
Self-organized straight nanowires of WO(3) have been epitaxially grown on muscovite mica in low super-saturation conditions. Morphology, structure and chemical composition of the prepared nanostructures have been investigated by scanning electron microscopy (SEM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS). SEM permits us to observe nanowire networks and substrate electron channeling patterns (ECP) simultaneously and thus to determine crystallographic direction of nanowire growth. The experimental results show that straight WO(3) nanowires are orientated preferentially parallel to two of three high symmetry crystallographic directions of mica [100] and [110] or [100] and [1 (1) over bar0]. XRD and XPS measurements indicated self-assembly of very thin nanowires of hexagonal tungsten bronze in the first stage of growth followed by the formation of stoichiometric WO(3). The growth mechanism has been studied as a function of different preparation conditions with special focus on the role of potassium ions present on the mica surface. Based on obtained results a growth model of tungsten oxide nanowires on mica is proposed.
- 出版日期2009-11-4
