Formation of conducting copper sulfide layers on polyamide 6 using polythionates and analysis of these layers

The formation of semiconductive and electrically conductive layers of copper sulfides, Cu(x)S, by sorption-diffusion on the surface of polyamide 6 (PA) using solutions of potassium polythionates-trithionate, K(2)S(3)O(6) tetrathionate, K(2)S(4)O(6) pentathionate, K(2)S(5)O(6), and dodecathionic acid, H(2)S(12)O(6), has been investigated. The measurement of IR and UV absorption spectra has shown that sulfur is sorbed on - it is diffused in the PA films in the form of polythionate anions. The concentration of sulfur in PA increases with the increase in the sulfurization time, the sulfur content in the polythionate molecules and the temperature of the sulfur precursor solution. concentrations of sulfur obtained in the polymer treated with a solution of dodecathionic acid (up to similar to 8 mmol/cm(3)) are significantly higher than those obtained in the PA films treated with the solutions of lower potassium polythionates (up to similar to 0.07-0.22 mmol/cm(3)). Copper sulfide layers are formed on the surface of the PA film if the sulfurized polymer is treated with a solution of copper(II / I) salts. The conditions of polymer initial sulfurization determine the concentration of copper in PA, the stoichiometric composition of Cu(x)S layers and the variation of the electrical sheet resistance of Cu(x)S layers. The concentration of copper in PA increases with the increase in the sulfurization time, the sulfur content in the polythionate anion and the temperature of the precursor solution, and varies from 0.0035 to similar to 8 mmol/cm(3). Ten Cu(x)S phases - chalcocite (Cu(2)S and Cu(1.96)S), anilite (Cu(7)S(4) and Cu(7)S(5)), djurleite (Cu(31)S(16) and Cu(19375)S), copper sulfide (CuS(2)), digenite (Cu(9)S(5)), yarrowite (Cu(9)S(8)) and covelline (CuS) - were identified on copper sulfide layers on the polymer surface by X-ray diffraction analysis. The electrical sheet resistance of Cu(x)S layers obtained decreases with the increase in the sulfurization duration and temperature, and the number of sulfur atoms in the polythionate anion.