Determination of the atomic structure of bimetallic Pt-Ag nanoparticles in metal-carbon catalysts by X-ray absorption spectroscopy data

Abstract

Determination of the atomic structure of bimetallic Pt-Ag nanoparticles in metal-carbon catalysts by X-ray absorption spectroscopy data

V.V. Pryadchenko, V.V. Srabionyan, A.D. Galustov, L.A. Avakyan, E.B. Mikheykina, Ya.V. Zubavichus, V.E. Guterman, L.A. Bugaev

Incoming article date: 29.03.2014

The atomic structure of bimetallic nanoparticles of Pt-Ag composition, which are the part of metal-carbon electro-catalysts PtAg/C, is studied by means of EXAFS spectroscopy using the suggested technique. These materials have been prepared by methods of consistent and simultaneous deposition of Ag and Pt atoms from aqueous ethylene glycol solutions of their salts with subsequent acid treatment. The values ​​of the structural parameters of the near environment of platinum atoms are determined. The nature of the distribution of components in nanoparticles is established. Cluster models of nanoparticles are constructed. The fraction of Pt atoms in the working shell and its dependance on preparation methods in each case are determined.

Keywords: Metal-carbon electrocatalysts, bimetallic nanoparticles, Catalysis, Platinum, X-ray absorption spectroscopy, atomic structure