Electrooxidation of methanol, ethanol, and formic acid was studied on three platinum-containing electrocatalysts: PtCu/C, Pt/(SnO₂/C), and Pt/C, Pt content being about 20 wt%. In all reactions, the integral specific activity of the catalysts, estimated from the results of cyclic voltammetry, grows in the Pt/C < Pt/(SnO₂/C) < PtCu/C row. The influence of the reagent nature subjected to electrooxidation is manifested both in the difference of the absolute rate values of the corresponding reactions, decreasing in the order CH₃OH > HCOOH > C₂H₅OH, and in the different ratio of these rates on different catalysts and at different potentials. Pt/(SnO₂/C) catalyst containing SnO₂ nanoparticles is the most active among the studied catalysts in methanol and formic acid electrooxidation reactions under potentiostatic conditions at the E = 0.60 V. Moreover, in formic acid electrooxidation reaction it is significantly superior to even the PtRu/C commercial catalyst. The reasons for the positive influence of Cu atoms and SnO₂ nanoparticles on the catalytic activity of platinum are presumably associated with different effects: Interaction of the d-orbitals of copper and platinum atoms in bimetallic nanoparticles and implementation of the bifunctional catalysis mechanism on the adjacent platinum and tin dioxide nanoparticles.

Bimetallic platinum-containing catalysts are deemed promising for electrolyzers and proton-exchange membrane fuel cells (PEMFCs). A significant number of laboratory studies and commercial offers are related to PtNi/C and PtCo/C electrocatalysts. The behavior of PtPd/C catalysts has been studied much less, although palladium itself is the metal closest to platinum in its properties. Using a series of characterization methods, this paper presents a comparative study of structural characteristics of the commercial PtPd/C catalysts containing 38% wt. of precious metals and the well-known HiSpec4000 Pt/C catalyst. The electrochemical behavior of the catalysts was studied both in a three-electrode electrochemical cell and in the membrane electrode assemblies (MEAs) of hydrogen–air PEMFCs. Both PtPd/C samples demonstrated higher values of the electrochemically active surface area, as well as greater specific and mass activity in the oxygen reduction reaction in comparison with conventional Pt/C, while not being inferior to the latter in durability. The MEA based on the best of the PtPd/C catalysts also exhibited higher performance in single tests and long-term durability testing. The results of this study conducted indicate the prospects of using bimetallic PtPd/C materials for cathode catalysts in PEMFCs.

The bimetallic PtRu nanoparticles deposited on the carbon support with the metals’ atomic ratio of 1:1 have been obtained by different liquid-phase synthesis methods. The metals’ mass fraction in the obtained PtRu/C catalysts is about 27%. The average size of the bimetallic nanoparticles ranges from 1.9 to 3.9 nm. The activity of the obtained PtRu/C catalysts in the methanol electrooxidation reaction as well as their tolerance to intermediate products of its oxidation have been studied. The sample synthesized by the polyol method has proved to be the most active material. The values of its electrochemical surface area and activity in the methanol electrooxidation reaction are 1.5–1.7 times higher than those of the commercial PtRu/C analogue. Nevertheless, the use of the polyol method leads to losses of the metals during the synthesis. Therefore, this method needs further optimization.

To obtain the PtRu/C electrocatalysts, the surfactant-free (wet) synthesis methods have been used. The structural-morphological characteristics and electrochemical behavior of the catalysts have been studied. The possibility of ranging the crystallite size from 1.2 to 4.5 nm using different reducing agents (ethylene glycol, ethanol, and isopropanol) has been shown. The effect of both the particles’ size and the mass fraction of the metal component on the electrochemical surface area (ESA), activity in the methanol electrooxidation reaction (MOR), and tolerance to its intermediate products has been studied. The simple and scalable surfactant-free synthesis method of the highly active PtRu/C electrocatalysts with a different mass fraction of metals, with their tolerance to intermediate products of the oxidation being 2.3 times higher than the commercial analogue, has been first proposed. The authors have succeeded in obtaining the PtRu/C catalysts with the nanoparticles’ size of less than 2 nm, characterized by the ultranarrow size and uniform spatial distributions over the support surface, thus having the ESA of more than 90 m²g_PtRu⁻¹.