Laser-induced metastable mixed phase of AuNi nanoparticles: a coherent X-ray diffraction imaging study.

J Synchrotron Radiat

Department of Physics and Photon Science and School of Materials Science and Engineering, Gwangju Institute of Science and Technology, 61005 Gwangju, Korea.

Published: May 2020


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Article Abstract

The laser annealing process for AuNi nanoparticles has been visualized using coherent X-ray diffraction imaging (CXDI). AuNi bimetallic alloy nanoparticles, originally phase separated due to the miscibility gap, transform to metastable mixed alloy particles with rounded surface as they are irradiated by laser pulses. A three-dimensional CXDI shows that the internal part of the AuNi particles is in the mixed phase with preferred compositions at ∼29 at% of Au and ∼90 at% of Au.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7206555PMC
http://dx.doi.org/10.1107/S1600577520001617DOI Listing

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