This article provides an overview of modern technologies and implemented projects in the field of renewable energy systems for the electrification of railway transport. In the first part, the relevance of the use of renewable energy on the railways is discussed. Various types of power-generating systems in railway stations and platforms along the track, as well as in separate areas, are considered. The focus is on wind and solar energy conversion systems. The second part is devoted to the analysis of various types of energy storage devices used in projects for the electrification of railway transport since the energy storage system is one of the key elements in a hybrid renewable energy system. Systems with kinetic storage, electrochemical storage batteries, supercapacitors, hydrogen energy storage are considered. Particular attention is paid to technologies for accumulating and converting hydrogen into electrical energy, as well as hybrid systems that combine several types of storage devices with different ranges of charge/discharge rates. A comparative analysis of various hybrid electric power plant configurations, depending on the functions they perform in the electrification systems of railway transport, has been carried out.

Ce_1−xZr_xO₂ oxides (x = 0.1, 0.25, 0.5) prepared via the Pechini route were investigated using XRD analysis, N₂ physisorption, TEM, and TPR in combination with density functional theory calculations. The Ni/Ce_1−xZr_xO₂ catalysts were characterized via XRD analysis, SEM-EDX, TEM-EDX, and CO chemisorption and tested in carbon dioxide methanation. The obtained Ce_1−xZr_xO₂ materials were single-phase solid solutions. The increase in Zr content intensified crystal structure strains and favored the reducibility of the Ce_1−xZr_xO₂ oxides but strongly affected their microstructure. The catalytic activity of the Ni/Ce_1−xZr_xO₂ catalysts was found to depend on the composition of the Ce_1−xZr_xO₂ supports. The detected negative effect of Zr content on the catalytic activity was attributed to the decrease in the dispersion of the Ni⁰ nanoparticles and the length of metal–support contacts due to the worsening microstructure of Ce_1−xZr_xO₂ oxides. The improvement of the redox properties of the Ce_1−xZr_xO₂ oxide supports through cation modification can be negated by changes in their microstructure and textural characteristics.

Highly dispersed 1.9 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} and 5 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} catalysts with an average particle size of 0.9 nm were prepared by sorption-hydrolytic precipitation. It was shown that the catalysts are active in the water gas shift reaction in a mixture simulating synthesis gas produced by steam reforming of natural gas. At an initial CO concentration of 10 vol % and a flow rate of 30000 ncm³ \({\text{g}}_{{{\text{cat}}}}^{{ - 1}}\) h^–1, outlet CO and CH₄ concentrations reach 2.5 and 0.01 vol %, respectively, over 1.9 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} at 325°C and 1.5 and 0.075 vol %, respectively, over 5 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} at 300°С. The observed reaction orders for CO and H₂O over 5 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} were found to be close to zero, and the apparent activation energy for both catalysts was 86 kJ/mol. Transmission electron microscopy of the catalysts showed that the narrow size distribution and high dispersion of the supported particles are retained during the reaction. However, some coarsening of Pt particles occurs, the average size increases to 1.4 and 1.6 nm for 1.9 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} and 5 wt % Pt/Ce_0.75Zr_0.25O_{2 – x}, respectively. For the catalysts after the reaction, the metallic Pt surface area values, measured by CO chemisorption and transmission electron microscopy, differ significantly. Most likely, it is caused by the presence of some of the surface Pt atoms in the oxidized state. It was shown that the temperature dependences of the turnover frequency in the water gas shift reaction per the length unit of the metal-support interface, coincide for catalysts 1.9 wt % Pt/Ce_0.75Zr_0.25O_{2 – x} and 5 wt % Pt/Ce_0.75Zr_0.25O_{2 – x}. Based on this, an assumption was made about the leading role of the Pt–Ce_0.75Zr_0.25O_{2 – x} boundary in the catalysis of the water gas shift reaction.

The paper presents a comparative study of the activity of magnetite (Fe₃O₄) and copper and cobalt ferrites with the structure of a cubic spinel synthesized by combustion of glycine-nitrate precursors in the reactions of ammonia borane (NH₃BH₃) hydrolysis and hydrothermolysis. It was shown that the use of copper ferrite in the studied reactions of NH₃BH₃ dehydrogenation has the advantages of a high catalytic activity and the absence of an induction period in the H₂ generation curve due to the activating action of copper on the reduction of iron. Two methods have been proposed to improve catalytic activity of Fe₃O₄-based systems: (1) replacement of a portion of Fe²⁺ cations in the spinel by active cations including Cu²⁺ and (2) preparation of highly dispersed multiphase oxide systems, involving oxide of copper.

The study is presented on the influence of the composition of a ceria-zirconia support on the structure and the activity in water-gas shift reaction of platinum catalysts (Pt/Ce_0.75Zr_0.25O₂ and Pt/Ce_0.4Zr_0.5Y_0.05La_0.05O₂). The structure diagnostics of the samples were performed using high-resolution transmission electron microscopy, powder X-ray diffraction, CO chemisorption and X-ray atomic pair distribution function method. It was shown that the catalysts contain highly dispersed platinum particles not exceeding 2 nm in size. Platinum particles supported on Ce_0.75Zr_0.25O₂ are smaller due to the higher specific surface area of the support. The catalysts Pt/Ce_0.75Zr_0.25O₂ and Pt/Ce_0.4Zr_0.5Y_0.05La_0.05O₂ proved to have similar efficiency while having the same platinum content. It was assumed that the catalysts supported on Ce_0.4Zr_0.5Y_0.05La_0.05O₂ demonstrate a slightly higher turnover frequency per platinum surface atom, but it is likely compensated by the difference in the supported metal particle size.