In comparison with the commercial palladium catalysts, the core–shell gold–palladium nanoparticles with subnanometer-thick palladium shells display superior activity and durability in catalyzing the oxygen reduction reaction, mainly due to the lattice tensile effect in palladium shells induced by the gold cores, which sufficiently balances the bond-breaking and bond-making steps of the oxygen reduction reaction process. e) Cyclic voltammetry of gold nanoparticles (upper part) and Pt/Au core-shell nanoparticles (lower part) in 0.1 M HClO 4 scanning the potential between 0. The deposition of palladium atoms gradually changes the surface property of gold seeds, and in particular, the catalytic reduction of palladium ions ceases when 3 palladium atomic layers are deposited on the gold cores. In this approach, owing to the catalysis of gold particles, the reduction of palladium precursors would only occur on the surface of gold cores, preventing the newly formed palladium atoms from self-nucleation. To this end, the construction of two metals in a core-shell/Janus nanostructure to coupling a plasmonic absorber (i.e. Herein, we report a gold-catalyzed strategy for the synthesis of core–shell gold–palladium nanoparticles with subnanometer-thick palladium shells towards oxygen reduction reaction. Copyright © 2008 John Wiley & Sons, Ltd.Ultrathin metal layers formed on seed particles with different lattice parameters usually exhibit enhanced catalytic performance for a given chemical reaction due to the sufficient lattice strain effect induced by the core region. Thus the originally low enhancement factor of Pd could be improved substantially. The enhancement factor of the ultrathin Pd shell was found to be over 5 × 10 4. The optimum-sized Au nanoparticles were utilized to further prepare Au–Pd core–shell ( )nanoparticles in order to greatly enhance the SERS activity of the Pd shell. Finite difference time domain (FDTD) calculationwas employed to explain the size-dependent SERS activity. Using pyridine as the probe molecule, the average enhancement factorcould reach up to 10 7. 2 The nanoparticle film with the size range of 120–135 nm showed the highest SERS activity with the excitation wavelength of 632.8 nm. These nanoparticles can be easily formed as a uniform thin film on glass carbon or gold substrates with an area larger than 1 mm. In this work, we report a facile synthesis route, structural characterization, and full atomistic simulations of gold-palladium nanoalloys. Recently, we utilized a simple seed-mediated growth method to synthesize monodisperse Au nanoparticles with controllable size from about 16 to 160 nm, which were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis spectroscopy. Gold nanoparticles (AuNPs) are among the most innovative catalysts, despite bulk Au metal being regarded as stable and inactive. Chemical Name: Gold Palladium Core-Shell Nanoparticles Purity: >99.99 APS: 80-100 nm (Size Customization possible) Form: Nanopowder/Nanodispersion Product. This paper covers the core-shell nanomaterials, mainly, polymer-core polymer shell, polymer-core metal shell, and polymer-core nonmetal shells. The optimization of surface-enhanced Raman scattering (SERS) activity of gold nanoparticles is essential for further enhancing SERS capability in terms of high sensitivity, stability and reproducibility.
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