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The global issue for proton exchange membrane fuel cell market development is a reduction in the device cost through an increase in efficiency of the oxygen reduction reaction occurring at the cathode and an extension of the service life of the electrochemical device. Losses in the fuel cell performance are due to various degradation mechanisms in the catalytic layers taking place under conditions of high electric potential, temperature, and humidity. This review is devoted to recent advances in the field of increasing the efficiency and durability of electrocatalysts and other electrode materials by introducing structured carbon components into their composition. The main synthesis methods, physicochemical and electrochemical properties of materials, and performance of devices on their basis are presented. The main correlations between the composition and properties of structured carbon electrode materials, which can provide successful solutions to the highlighted issues, are revealed.

Platinum electrocatalysts on graphene-like supports have recently attracted research interest as components of electrochemical devices based on hydrogen oxidation reactions in acid media due to their improved electrochemical properties, high stability, and conductivity. Within the current work, hydrogen adsorption and the recombination effects of a proton and hydroxonium on a graphene-based electrocatalyst were investigated using density functional theory. The interaction between ions and the platinum surface was simulated for various configurations, including different initial ion distances and angles relative to the surface of the graphene sheet as well as different adsorptions on various Pt atoms (vertices or faces for Pt13 and Pt14 nanoclusters). Then, the geometry optimization was performed. Changes in the density of states during the reactions were studied to analyze the occurrences and alterations of the interactions. A comparative analysis of the obtained adsorption energies of H+ and H3O+ with experimental data was conducted. The energy was calculated to be less in absolute value, and intermediates were more stable in adsorption models with the H–Pt–Gr angle of 90° than in models with the angle of 180°. Strong chemical bonding for models with H–Pt distances less than 2 Å was observed from the DOS.

One of the most important problems in the development of proton-exchange membrane fuel cells (PEMFCs) is the selection of an efficient support material to serve as the electrocatalyst, which can ensure PEMFCs’ durability at low active metal loading, with minimal changes in the electrochemical surface and conductivity during long-term operations. Carbon nanostructures are now widely used in PEMFCs as such support materials, including carbon nanotubes (CNTs). In order to estimate the effect of the geometric parameters of a CNT-based support on the resulting size distribution of platinum nanoparticles for given synthesis conditions, in this work, we propose a semi-empirical model that assumes a random uniform distribution of platinum particles over the CNT surface. Based on the obtained distribution, the electrochemically active surface area (EASA) of the electrocatalyst is calculated and further used to evaluate the performance of the catalytic layer (CL) in the PEMFC. The applicability of the proposed model for calculating the parameters of CNT-based CLs and the output electrochemical characteristics of PEMFCs is shown.

Pt/C and Pt/x-SnO2/C catalysts (where x is mass content of SnO2) were synthesized using a polyol method. Their kinetic properties towards oxygen reduction reaction were studied by a rotating disk electrode (RDE) technique in a temperature range from 1 to 50 °C. The SnO2 content of catalyst samples was 5 and 10 wt.%. A quick evaluation of the catalyst activity, electrochemical behavior and average number of transferred electrons were performed using the RDE technique. It has been shown that the use of x-SnO2 (through modification of the carbon support) in a binary system together with Pt does not reduce the catalyst activity in the temperature range of 1–30 °C. The temperature rising up to 50 °C resulted in composite catalyst activity reduction at about 30%.

A detailed study of the structure, morphology and electrochemical properties of Pt/C and Pt/x-SnO2/C catalysts synthesized using a polyol method has been provided. A series of catalysts supported on the SnO2-modified carbon was synthesized and studied by various methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical methods, and fuel cell testing. The SnO2 content varies from 5 to 40 wt %. The TEM images, XRD and XPS analysis suggested the Pt-SnO2 hetero-clusters formation. The SnO2 content of ca. 10% ensures an optimal catalytic layer structure and morphology providing uniform distribution of Pt-SnO2 clusters over the carbon support surface. Pt/10wt %-SnO2/C catalyst demonstrates increased activity and durability toward the oxygen reduction reaction (ORR) in course of accelerated stress testing due to the high stability of SnO2 and its interaction with Pt. The polymer electrolyte membrane fuel cell current−voltage performance of the Pt/10wt %-SnO2/C is comparable with those of Pt/C, however, higher durability is expected.