We report on the existence of MoS2 and WS2 micro- and nanotubes alloyed wit
h gold and silver. The tubes have been grown by chemical transport reaction
with iodine as a transport agent. While the undoped inorganic tubes grow b
y spiral rolling of the molecular layers, the presence of noble metals can
partially or completely remove the chirality. The molecular layers grow in
the form of coaxial cylinders. The noble metal is situated inside the walls
of the tubes. It influences the longitudinal terminations of the tubes and
increases the wall thickness. Distortion of every second van der Waals gap
reveals that staging is present. Stop of chirality in alloyed inorganic tu
bes appears to be strongly coupled with the expansion of VdW gaps.
The existence of MxMoS2 and MxWS2; (M: Au, Ag) ternary compounds, which are
not known in the usual plane layered structures, gives evidence that the c
ylindrical geometry of crystals can stabilize new compounds and changes the
chemistry as well as the physical properties of the materials.