RFBR-NSFC Project №21-53-53034

(2021-2023)

The project under the joint leadership of Prof. O. V. Levin and Prof. Yang Peixia of Harbin Polytechnic University is devoted to the creation of new materials that accelerate the oxygen electroreduction reaction in fuel cells. The rapid expansion of global energy demand and the constant growth of carbon dioxide emissions have led to the rapid development of clean energy technologies aimed at preserving energy and reducing harmful emissions. Among actively developing new technologies, hydrogen-oxygen fuel cells with proton exchange membranes (PEMFC) and metal-air batteries are the most efficient energy conversion and storage systems. In both PEMFCs and zinc-air or aluminum-air batteries, the reduction reactions and oxygen release that occur at the cathode are the main electrochemical processes that determine the performance of the entire system. The slow kinetics of these reactions requires the use of catalysts, which are usually expensive platinum group metals, which seriously limits the further use and development of energy sources relying on these reactions. Catalyst performance largely determines the overall performance and efficiency of energy conversion devices, so the development of catalyst materials with low cost, high activity, and high stability is crucial to the widespread application of these new energy technologies.

In recent years, the use of carbon materials in electrocatalysis has attracted considerable attention due to their typical advantages, including availability of raw materials, high electrical conductivity, possibility to tune structure, and good chemical stability. The composition and physicochemical properties of precursors used for pyrolytic production of carbon material have a critical influence on the properties of such electrocatalysts. Among the precursors, the nitrogen-containing polymers whose directed synthesis is proposed in the current project are particularly prominent. As a result of pyrolysis, nitrogen-containing polymers are converted into nitrogen-doped carbon materials. The introduction of nitrogen improves the performance of carbon materials, because when electron-rich nitrogen enters the carbon lattice at the vacancies of the carbon atom, the heteroatom brings additional electron density to the delocalized π-system of carbon materials without destroying the sp2 hybridization structure of the graphene plane. The excess electrons increase the electrical conductivity. Inclusion of nitrogen can also change the hydrophilicity and hydrophobicity of the catalyst and contribute to its better contact with the electrolyte and increase ionic conductivity. The structure and composition of nitrogen-containing polymers can be adjusted at the molecular level. This makes it possible to introduce many heteroatoms, change the electronic structure of carbon materials, and promote the formation of potentially active catalytic centers. The presence of nitrogen atoms also facilitates the alloying of the carbon material with metals, the formation of a metal-nitrogen coordination structure, or the anchoring of metal particles, which increases the total catalytic activity. In addition, using nitrogen-containing polymers, it is possible to create a multidimensional ordered carbon material, which provides an opportunity to design highly efficient porous carbon electrocatalysts. Consequently, the production of carbon materials using nitrogen-containing polymers as precursors makes it possible to solve several critically important problems in the fields of energy storage, adsorption with gas trapping, and electrochemical catalysis.

This project will be carried out in collaboration with the Harbin Institute of Technology (China) and will make use of China's extensive experience in developing fuel cells and air-zinc batteries for the preparation of highly efficient catalysts based on non-precious metals. By cooperating on this project, it will be possible to significantly increase the level of research on non-precious metal catalysts and narrow the gap with leading countries in this field. This project is also important for promoting the industrialization of fuel cells and metal-air batteries through the expected acquisition of techniques for the synthesis of new high-performance catalysts based on non-precious metals.

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