1. Pt Diffusion Dynamics for the Formation Cr–Pt Core–Shell Nanoparticles
- Author
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Gupta, G., Iqbal, P., Yin, F., Liu, J., Palmer, R. E., Sharma, S., Leung, K. Cham-Fai, Mendes, P. M., Gupta, G., Iqbal, P., Yin, F., Liu, J., Palmer, R. E., Sharma, S., Leung, K. Cham-Fai, and Mendes, P. M.
- Abstract
Layered core–shell bimetallic Cr–Pt nanoparticles were prepared by the formation and later reduction of an intermediate Pt-ion-containing supramolecular complex onto preformed Cr nanoparticles. The resultant nanoparticles were characterized by X-ray diffraction analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, and aberration-corrected scanning transmission electron microscopy. The results are consistent with the presence of Pt diffusion during or after bimetallic nanoparticle formation, which has resulted in a Pt/Cr-alloyed core and shell. We postulate that such Pt diffusion occurs by an electric-field-assisted process according to Cabrera–Mott theory and that it originates from the low work function of the preformed oxygen-defective Cr nanoparticles and the rather large electron affinity of Pt.
- Published
- 2015