Morphology-Controlled Growth of Crystalline Ag-Pt-Alloyed Shells onto Au Nanotriangles and Their Plasmonic Properties

Xiaobin Xie; Marijn A van Huis; Alfons van Blaaderen

doi:10.1021/acs.jpcc.3c02897

Morphology-Controlled Growth of Crystalline Ag-Pt-Alloyed Shells onto Au Nanotriangles and Their Plasmonic Properties

J Phys Chem C Nanomater Interfaces. 2023 Aug 3;127(32):16052-16060. doi: 10.1021/acs.jpcc.3c02897. eCollection 2023 Aug 17.

Authors

Xiaobin Xie¹, Marijn A van Huis¹, Alfons van Blaaderen¹

Affiliation

¹ Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands.

Abstract

The surface plasmon resonance of noble-metal nanoparticles depends on nanoscale size, morphology, and composition, and provides great opportunities for applications in biomedicine, optoelectronics, (photo)catalysis, photovoltaics, and sensing. Here, we present the results of synthesizing ternary metallic or trimetallic nanoparticles, Au nanotriangles (Au NTs) with crystalline Ag-Pt alloyed shells, the morphology of which can be adjusted from a yolk-shell to a core-shell structure by changing the concentration of AgNO₃ or the concentration of Au NT seeds, while the shell thickness can be precisely controlled by adjusting the concentration of K₂PtCl₄. By monitoring the growth process with UV-vis spectra and scanning transmission electron microscopy (STEM), the shells on the Au NT-Ag-Pt yolk-shell nanoparticles were found to grow via a galvanic replacement synergistic route. The plasmonic properties of the as-synthesized nanoparticles were investigated by optical absorbance measurements.