Correlating catalytic activity of Ag-Au nanoparticles with 3D compositional variations.
نویسندگان
چکیده
Significant elemental segregation is shown to exist within individual hollow silver-gold (Ag-Au) bimetallic nanoparticles obtained from the galvanic reaction between Ag particles and AuCl4(-). Three-dimensional compositional mapping using energy dispersive X-ray (EDX) tomography within the scanning transmission electron microscope (STEM) reveals that nanoparticle surface segregation inverts from Au-rich to Ag-rich as Au content increases. Maximum Au surface coverage was observed for nanoparticles with approximately 25 atom % Au, which correlates to the optimal catalytic performance in a three-component coupling reaction among cyclohexane carboxyaldehyde, piperidine, and phenylacetylene.
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ورودعنوان ژورنال:
- Nano letters
دوره 14 4 شماره
صفحات -
تاریخ انتشار 2014