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A carbon supported PtCux/C catalyst, which demonstrates high activity in the oxygen electroreduction and methanol electrooxidation reactions in acidic media, has been obtained using a method of chemical reduction of Pt (IV) and Cu (2+) in the liquid phase. It has been found that the potential range of the preliminary voltammetric activation of the PtCux/C catalyst has a significant effect on the de-alloyed material activity in the oxygen electroreduction reaction (ORR). High-resolution transmission electron microscopy (HRTEM) demonstrates that there are differences in the structures of the as-prepared material and the materials activated in different potential ranges. In this case, there is practically no difference in the composition of the PtCux-y/C materials obtained after activation in different conditions. The main reason for the established effect, apparently, is the reorganized features of the bimetallic nanoparticles’ surface structure, which depend on the value of the limiting anodic potential in the activation process. The effect of the activation conditions on the catalyst’s activity in the methanol electrooxidation reaction is less pronounced.

This review considers the features of the catalysts with different nanoparticle structures architecture transformation under the various pre-treatment types. Based on the results of the publications analysis, it can be concluded that the chemical or electrochemical activation of bimetallic catalysts has a significant effect on their composition, microstructure, and catalytic activity in the oxygen reduction reaction. The stage of electrochemical activation is recommended for use as a mandatory catalyst pre-treatment to obtain highly active de-alloyed materials. The literature is studied, which covers possible variants of the structural modification under the influence of thermal treatment under different processing conditions. Additionally, based on the literature data analysis, recommendations are given for the thermal treatment of catalysts alloyed with various d-metals.

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The present study, concerned with high-performance ORR catalysts, may be a valuable resource for a wide range of researchers within the fields of nanomaterials, electrocatalysis, and hydrogen energy. The objects of the research are electrocatalysts based on platinum–copper nanoparticles with onion-like and solid-solution structures. To evaluate the functional characteristics of the catalysts, the XRD, XRF, TEM, HAADF-STEM, and EDX methods, as well as the voltammetry method on a rotating disk electrode have been used. This work draws the attention of researchers to the significance of applying a protocol of electrochemically activating bimetallic catalysts in terms of the study of their functional characteristics on the rotating disk electrode. The choice of the potential range during the pre-cycling stage has been shown to play a crucial role in maintaining the durability of the catalysts. The activation of the PtCu/C catalyst during cycling of up to 1.0 V allows for an increase in the durability of the catalysts with onion-like and solid-solution structures of nanoparticles by 28% and 23%, respectively, as compared with activation of up to 1.2 V.