Correlation between theoretical data and experimental selective properties of PtAg core-shell nanoparticles for oxygen reduction reactions

• DFT evidence that the most stable structure for PtAg bimetallic is core–shell.
• The core–shell structure PtAg was elucidated using molecular dynamics.
• PtAg have a good performance for the ORR in presence of glucose in alkaline medium.

In previous reports, PtAg core–shell catalysts have shown selective properties for oxygen reduction reactions in the presence of 0.1 M glucose interference in basic media. This characteristic has allowed for the operation of microfluidic fuel cells with only one feeding stream mixing fuel and oxidant. In this work, molecular dynamics (MD) and density functional theory (DFT) were used to explain the stability and conductive properties of nanoparticles. Characterization via XRD, XPS and STEM, electrochemical tests for oxygen reduction reactions in the absence and presence of glucose, and testing results from microfluidic fuel cell are also presented. The structural simulation agrees with the experimental data, showing core–shell formation from an alloy nanoparticle after heating. In addition, the electronic properties of the PtAg core–shell nanoparticles are very similar to those of the Pt nanoparticles.