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In this work, we investigated the formation of Tl-Se layers followed by doping with metal cations. A two-stage adsorption/diffusion process used to form Tl-Se layers involves (a) selenization in potassium selenotrithionate solution followed by (b) treatment with Tl+ precursor solutions. These layers have been successfully doped with Cu+/Cu2+, Ga3+ and Ag+ cations using a cation exchange reaction. The resulting chemical compositions of Tl-Se and Tl-M-Se (M = Cu, Ga, Ag) layers were investigated using the EDS and AAS methods. The bulk elemental composition and the Tl/Se molar ratio of the Tl-Se layers varied with the concentration of the Tl+ precursor solution, the exposure time in the Tl+ precursor solution, and the form of the Tl+ in the solution, whereas the EDS analysis showed that the surface was slightly enriched in thallium. The optical properties of the formed layers were studied. These layers were identified using room temperature reflection spectrum, the values of absorption edge, bandgap (Eg), band tail width (Urbach energy, EU) of the localised states, Steepness parameter (σ) and electron–phonon interaction (Ee-p).

Mixed cadmium tellurides–cadmium sulfide thin layers were formed on the polyamide PA 6. Monotelluropentathionic acid (H2TeS4O6) was used as a precursor of tellurium and sulfur. A low-temperature, nontoxic, and cost-effective SILAR method was applied. Cadmium telluride (CdTe) and sulfide (CdS) layers were formed through the consecutive reactions of sorbed/diffused chalcogens species from telluropentathionate anion (TeS4O62−) with functional groups of polyamide and alkaline cadmium sulfate. The pseudo-second-order rate and Elovich kinetic models were the best fit to quantify an uptake of chalcogens and cadmium on PA 6. The effects of chalcogens and Cd on the structure and optical properties of PA 6 were characterized using UV-Vis and IR spectra. The clear changes of these properties depended on the concentration and exposure time in the precursor solutions. Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy were applied in order to evaluate the effect of the chalcogen species on the changes in structure of polyamide 6 films, depending on the exposure time in the solution of the chalcogens precursor and its concentration. The optical bandgap energy of the formed layers was found to be in the order of 1.52–2.36 eV. Studies by scanning electron microscopy and atomic force microscopy reveal that the diameter of the average grain is approximately 30 nm. The grains are conical in shape and unevenly distributed all over the surface of the substrate.

Mixed cadmium tellurides – cadmium sulfides thin layers were formed on the polyamide PA 6. Monotelluropentathionic acid (H2TeS4O6) was used as precursor of tellurium and sulfur. We applied a low-temperature, nontoxic and cost-effective SILAR method. Cadmium telluride (CdTe) and sulfide (CdS) layers were formed through consecutive reactions of sorbed/diffused chalcogens species from telluropentathionate anion (TeS4O62–) with functional groups of polyamide and alkaline cadmium sulfate. The pseudo-second-order rate and Elovich kinetic models best fitted to quantify an uptake of chalcogens and cadmium on PA6. The effects of chalcogens and Cd on the structure and optical properties of PA6 were characterized using UV/Vis and IR spectra. The clear changes of these properties found in dependence on the concentration and exposure time in precursor's solutions. Fourier transform infrared spectroscopy and an ultraviolet-visible spectroscopy were applied in order to evaluate the effect of the chalcogens having particles on the changes in structure of polyamide 6 films depending on the exposure time in the solution of the chalcogens precursor and its concentration. The optical band gap energy of formed layers was found to be in the order of 1.52–2.36 eV. Studies of scanning electron microscopy and atomic force microscopy reveal that the diameter of the average grain is about 30 nm. The grains are conical in shape and unevenly distributed all over the surface of the substrate.