Toward Smaller Aqueous-Phase Plasmonic Gold Nanoparticles: High-Stability Thiolate-Protected â¼4.5 nm Cores.
Langmuir
; 35(32): 10610-10617, 2019 Aug 13.
Article
em En
| MEDLINE
| ID: mdl-31299160
ABSTRACT
Most applications of aqueous plasmonic gold nanoparticles benefit from control of the core size and shape, control of the nature of the ligand shell, and a simple and widely applicable preparation method. Surface functionalization of such nanoparticles is readily achievable but is restricted to water-soluble ligands. Here we have obtained highly monodisperse and stable smaller aqueous gold nanoparticles (core diameter â¼4.5 nm), prepared from citrate-tannate precursors via ligand exchange with each of three distinct thiolates 11-mercaptoundecanoic acid, α-R-lipoic acid, and para-mercaptobenzoic acid. These are characterized by UV-vis spectroscopy for plasmonic properties; Fourier transform infrared (FTIR) spectroscopy for ligand-exchange confirmation; X-ray diffractometry for structural analysis; and high-resolution transmission electron microscopy for structure and size determination. Chemical reduction induces a blueshift, maximally +0.02 eV, in the localized surface plasmon resonance band; this is interpreted as an electronic (-) charging of the monolayer-protected cluster (MPC) gold core, corresponding to a -0.5 V change in electrochemical potential.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Langmuir
Assunto da revista:
QUIMICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos