The effect of thermal treatment on the atomic structure of core–shell PtCu nanoparticles in PtCu/C electrocatalysts

• Published in: Physics of the solid state 2017-08, Vol.59 (8), p.1666-1673
• Main Authors: Pryadchenko, V. V., Belenov, S. V., Shemet, D. B., Volochaev, V. A., Srabionyan, V. V., Avakyan, L. A., Tabachkova, N. Yu, Guterman, V. E., Bugaev, L. A.
• Format: Article
• Language: English
• Subjects: Analysis; Atomic Clasters; Atomic structure; Bimetals; Catalysts; Chemical reduction; Chemical synthesis; Copper; Copper oxides; Electrocatalysts; Ethylene glycol; Ethylene glycols; Heat treatment; Intermetallic compounds; Microphotographs; Nanoparticles; Physics; Physics and Astronomy; Solid solutions; Solid State Physics; Transmission electron microscopy; X-ray diffraction
• ISSN: 1063-7834; 1090-6460
• DOI: 10.1134/S1063783417080200

PtCu/C electrocatalysts with bimetallic PtCu nanoparticles were synthesized by successive chemical reduction of Cu 2+ and Pt(IV) in a carbon suspension prepared based on an aqueous ethylene glycol solution. The atomic structure of as-prepared PtCu nanoparticles and nanoparticles subjected to thermal treatment at 350°C was examined using Pt L 3 and Cu K EXAFS spectra, transmission electron microscopy (TEM), and X-ray powder diffraction (XRD). The results of joint analysis of TEM microphotographs, XRD profiles, and EXAFS spectra suggest that the synthesized electrocatalysts contain PtCu nanoparticles with a Cu core–Pt shell structure and copper oxides Cu 2 O and CuO. Thermal treatment of electrocatalysts at 350°C results in partial reduction of copper oxides and fusion of bimetallic nanoparticles with the formation of both homogeneous and ordered PtCu solid solutions.