Solving the structure of PtCo nanoparticles with EXAFS

MARTÍN DANIEL MIZRAHI; LISANDRO J. GIOVANETTI; JOSE MARTIN RAMALLO LOPEZ; SHEVCHENKO, ELENA; FÉLIX G. REQUEJO

Campinas

Conferencia; 25th Reunion Annual de Usuarios LNLS 25RAU; 2015

We resolved the structure of core-shell bimetallic Co-Pt nanoparticles using Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy at the Co-K and Pt-L3 edges. Using the results of the EXAFS fits at both edges and theoretical models we could determine the core and shell composition as well as the inner and outer radius of two different bimetallic nanoparticles obtained varying the synthesis conditions. The only compatible structure with our results is a CoPt3@Pt core-shell nanoparticle. Our models are supported by X-ray fluorescence, Transmition Electron Microscopy and Small Angle X-ray Scattering results