Characterization of Pd and Pd@Au core-shell nanoparticles using atom probe tomography and field evaporation simulation

• Published in: Journal of alloys and compounds Vol. 831; p. 154721
• Main Authors: Kim, Se-Ho, Jang, Kyuseon, Kang, Phil Woong, Ahn, Jae-Pyoung, Seol, Jae-Bok, Kwak, Chang-Min, Hatzoglou, Constantinos, Vurpillot, François, Choi, Pyuck-Pa
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.08.2020; Elsevier BV; Elsevier
• Subjects: Atom probe tomography; Chemical composition; Computer simulation; Condensed Matter; Core-shell particles; Data acquisition; Evaporation; Field evaporation; Gold; Image contrast; Mathematical models; Nanoparticles; Numerical simulation; Palladium; Physics; Simulation; Tomography; Nanoparticles; Numerical simulation; Atom probe tomography; Field evaporation
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2020.154721

We report on atom probe tomography analyses of Pd and Pd@Au nanoparticles embedded in a Ni matrix and the effects of local evaporation field variations on the atom probe data. In order to assess the integrity of the reconstructed atom maps, we performed numerical simulations of the field evaporation processes and compared the simulated datasets with experimentally acquired data. The distortions seen in the atom maps for both Pd and Pd@Au nanoparticles could be mostly ascribed to local variations in chemical composition and elemental evaporation fields. The evaporation field values for Pd and Ni, taken from the image hump model and assumed in the simulations, yielded a good agreement between experimental and simulation results. In contrast, the evaporation field for Au, as predicted from the image hump model, appeared to be substantially overestimated and resulted in a large discrepancy between experiments and simulations. •APT measurements and numerical simulations of the field evaporation processes of Pd and Pd@Au core-shell nanoparticles in a Ni matrix were performed.•While Pd nanoparticle showed only little distortion in the reconstructed atom maps, Pd@Au core-shell nanoparticle showed strong distortions.•The evaporation field of Au (53 V nm−1) predicted from the image hump model yielded strong discrepancies between experimental and simulation results for Pd@Au nanoparticles.