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An algorithm for analyzing double-crystal rocking curves from the near-surface layers of monocrystals has been proposed, and corresponding software has been developed. It is taken into account that to obtain correct results, both coherent and diffuse components of X-ray scattering need to be considered. The possibility of simultaneous analysis of rocking curves from several reflections is provided. To approximate experimental rocking curves with theoretical ones, an approach that simultaneously uses three different approximation methods has been utilized. The effectiveness of the proposed approach is confirmed by verifying the uniqueness of the obtained results.

In this work, the Perovskite powders LaFe0.5Cr0.5O3 with a space group of P m - 3 m was obtained by the sol-gel method. The nanoscale powders of LaFe0.5Cr0.5O3 have been tested as a cathode material for electrochemical supercapacitors. The CVA and charge-discharge curves were obtained at 0.5 mV/s to 16 mV/s and 0.5 mA/s to 16 mA/s scan rates accordingly. It is established that the cathode material LaFe0.5Cr0.5O3 demonstrates the specific capacity up to 16 F/g at a discharge scan rate 0.5 mV/s. Additionally, the maximum of the specific capacity was calculated and it is determined that C is 29.26 F/g, and the specific capacity of double electric layer CDEL is 3.44 F/g. It was determined that the contribution of the redox reactions in specific capacity is 88 %. The Nyquist plots and Mott-Schottky plots for LaFe0.5Cr0.5O3 were obtained. They consist of two parts that correspond to a different type of conductivity. Thus, it is established that LaFe0.5Cr0.5O3 shows different types of conductivity depending on the applied potential. The received values of flat band potential are -1.00 V and 0.16 V for n-type and p-type of conductivity accordingly.

Nanoscale powders of LaFe0.5Cr0.5O3 with perovskite structure were synthesized by sol-gel combustion method in this work. From X-rays phase analysis obtained material was consisted of one phase LaFe0.5Cr0.5O3 (space group P m -3 m). The average size of RCS of test material is 21 nm. Specific surface area is 14 m2/g. The average particle size is 63.7 nm by approximation that particles form is spherical. Nanoscale powders of LaFe0.5Cr0.5O3were tested as cathode material for lithium power sources. The cathode material demonstrates the specific power capacity of 571 A•h/kg when the discharge of the source is up to 0.5V. Keywords: sol-gel method, galvanostatic discharge, impedance, specific capacity.