Effect of the PtCu/C electrocatalysts initial composition on their activity in the de-alloyed state in the oxygen reduction reaction

The promising ORR electrocatalysts with the low platinum content have been obtained by a simple method in one pot. The morphology of Pt-based nanoparticles supported on carbon was controlled to enhance the catalytic performance in oxygen reduction reaction (ORR). A detailed study of the microstructural characteristics and electrochemical behavior of the de-alloyed electrocatalysts made it possible to obtain a correlation between the effect of PtCu/C materials initial composition and their ORR activity. It has been established that the initial content of the alloying component has a significant effect on the structural reorganization of bimetallic nanoparticles. Electrochemical study results showed that the ORR performance of de-alloyed PtCu/C catalyst with large Cu content in the initial structure was better than that of de-alloyed PtCu/C catalysts with low Cu content due to the morphology advantages. A successful reorganization of NPs structure increased the ORR activity of the de-alloyed catalysts by two times. A presented approach can be applied to design of different ORR electrocatalysts based on the PtM nanoparticles. • Facile and simple synthesis of high active Pt-based electrocatalysts. • De-alloyed Pt–Cu nanoparticles with similar Cu content show different catalytic ORR-activity. • The more copper in the initial PtCu NPs, the more active the de-alloyed catalyst is. • De-alloyed NPs “remember” their initial composition, which affects the final structure and ORR activity.