Study of Supported PtCu and PdAu Bimetallic Nanoparticles Using In-Situ X-ray Tools†

摘要: A combination of two synchrotron X-ray techniques, absorption spectroscopy (XAS), and pair distribution function analysis (PDF) with complementary Fourier transform infrared (FTIR) measurement, was used to characterize the composition distributions PdAu PtCu bimetallic particles after treatment in H2 or CO presence these gases. This is first reported application PDF study supported nanoparticles. We found that XAS informative determining component an initial sample, but better suited following changes upon changing gas environment. Thus, surface a particle about 2.5 nm be enriched Cu, while core bimetallic. There no evidence component-segregated core−shell structure. Treatment caused enrichment Pt layer, concomitant migration Cu core. The average si...