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The article presents the results of the preparation and study of a gel-polymer electrolyte based on lignin obtained from Pinus sylvestris. Sulfonation and subsequent chlorination of lignin make possible implementation of the principle of mono-ionic conductivity in a natural biopolymer matrix, which provides predominantly cationic conductivity of the electrolyte. Based on the results of the qualitative and quantitative analysis of the synthesized samples, the mechanisms of the chemical conversion of the biopolymer, the structure models of the converted fragments of macromolecules, as well as the quantum-chemical calculation of their electronic and geometric parameters are presented. The key electronic characteristics of the gel polymer electrolytes (GPE) based on a composite of lignins with 20 wt.% polyvinyl alcohol are determined by impedance spectroscopy. The maximum value of the specific volume conductivity is 2.48 × 10−4 S cm−1, which is comparable with most commercial electrolytes of this type, but at the same time, record values are reached in the number of lithium cation transfer tLi+ of 0.89. The studies allow to identify the basic laws of the effect of chemical modification on the structure of GPE and describe the mechanism of ionic conductivity.

The aim of this work is preparation and investigation of copper conductive paths by printing with a different type of functional ink. The solutions based on copper-containing complex compounds were used as inks instead of dispersions of metal nanoparticles. Thermal characteristics of synthesized precursors were studied by thermogravimetry in an argon atmosphere. Based on the comparison of decomposition temperature, the dimethylamine complex of copper formate was found to be more suitable precursor for the formation of copper layers. Structure and performance of this compound was studied in detail by X-ray diffraction, test of wettability, printing on flexible substrate, and electrical measurements.

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The electrochemical method was used to synthesize hematite (α-Fe2O3 nanoparticles in the 0.1 M NaCl solution. The α-Fe2O3 were synthesized by dissolution the iron anode with formation the Fe(OH)x and its calcinations at different temperatures. The samples were characterized by means by X-ray diffraction (XRD), Raman and UV-vis spectroscopy, electron microscopy, EDX and FTIR. The photocatalytic oxidation of the mordant dye Chrome blue (CB) using electrochemical synthesize hematite was studied under ultraviolet light (UV-light) irradiations. The effect of hematite calcination temperature and hydrogen peroxide concentration on photocatalytic degradation of chrome blue was carried out. Increasing the annealing temperature are increases the degree of dye decolorization which connected with the gradually increasing proportion of the crystalline phase at the expense of the amorphous phase.

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