Self-organized tungsten oxide nanowires on muscovite mica were investigated by means of SEM, XRD and XPS. It is shown that the nanowires are self-organized in the directions parallel to the main mica crystallographic directions.
They are preferentially orientated in only two of the three high symmetry crystallographic directions of muscovite mica, i.e. [100] and [110] or [100] and [1-10] due to the monoclinic structure of muscovite which is ranked among dioctahedral types of mica. The XRD results showed that the nanowire growth begins by formation of a very thin and narrow nanorod of hexagonal tungsten oxide bronze, and then it continues laterally and in thickness by formation of successive layers of tungsten trioxide.
Chemical composition of thick nanowires was confirmed by means of XPS pointing to stoichiometric WO3