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Title: An integrated experimental and theoretical study on the optical properties of uniform hairy noble metal nanoparticles
We report a viable route to plasmonic nanoparticles with well-controlled sizes, shapes, and compositions. A series of monodisperse Ag and Au nanoparticles capped with polystyrene chains ( i.e. , “hairy” nanoparticles) are crafted by capitalizing on star-like diblock copolymers as nanoreactors. Such monodisperse nanoparticles render an accurate absorption spectrum, providing a strong basis for theoretical investigation into their optical properties. By combining the experimental study with the three-dimensional finite element calculation of electromagnetic field distributions, the contributions of both intra-band and inter-band transitions to plasmonic absorption are revealed. The calculated absorption spectra perfectly reproduce the experimental observations, including the peak positions, shapes, and trends of peak shifting or broadening as a function of nanoparticle sizes. The influences of nanoparticle dimensions and surface ligands on plasmonic absorption of metallic nanoparticles are also systematically explored.  more » « less
Award ID(s):
1709420
PAR ID:
10098709
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
10
Issue:
48
ISSN:
2040-3364
Page Range / eLocation ID:
22750 to 22757
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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