Formation and Characterization of Mixed Copper Sulfide – Copper Telluride Layers on the Polyamide 6 Film Surface

Abstract

By a study of IR and UV absorption spectra it is shown that the telluropentathionate anions are sorbed-diffused into the
polyamide 6 films if they are treated with the water solutions (0.01 mol⋅dm–3 − 0.1 mol⋅dm–3, 20 °C) of sodium
telluropentathionate, Na2TeS4O6, or telluropentathionic acid, H2TeS4O6. The concentration of sorbed telluropentathionate
ions increases with the increase in duration of treatment and temperature of a TeS4O6
2– containing solution. The
mixed copper sulfide – copper telluride, CuxS – CuyTe, layers are formed in the surface of polyamide 6 film if the
chalcogenized polymer is treated with Cu(II/I) salt solution (10 min, 78 °C): the anionic particles TeS4O6
2– containing
tellurium and sulfur atoms of low oxidation state react with the copper(II/I) ions. The conditions of a polymer initial
chalcogenation determine the amount of copper and the composition of chalcogenide layer: the amount of copper in the
chalcogenide layer increases with the increase of initial chalcogenation duration and the concentration of solution. The
results of UV-VIS absorption spectra and X-ray structural analysis confirmed the formation of mixed copper sulfide –
copper telluride layers in the surface of polyamide 6. The phase composition of layer changes depending on the
conditions of the polymer initial treatment in a TeS4O6
2– solution. Three copper sulfide phases, Cu7S4, Cu1.9375S, Cu1.8S,
and four copper telluride phases, Cu2Te, Cu3Te2, CuTe, Cu2.72Te2, were identified in the composition of the layers by
X-ray diffraction. The regularities determined enable formation by sorption-diffusion method of electrically conductive
(6.0⋅103 kΩ/ – 1.0 kΩ/) copper sulfide – copper telluride layers of desirable composition and conductivity using the
solutions of telluropentathionates as a polyamide 6 chalcogenation agents.