Metallic-Like Stoichiometric Copper Sulfide Nanocrystals: Phase and Shape Selective Synthesis, Near-Infrared Surface Plasmon Resonance Properties and Their Modeling
Abstract
In the realm of semiconductor nanomaterials, a crystal lattice heavily doped with cation/anion vacancies or ionized atomic impurities is considered to be a general prerequisite to accommodating excess free carriers that can support localized surface plasmon resonance (LSPR). Here, we demonstrate a surfactant-assisted nonaqueous route to anisotropic copper sulfide nanocrystals, selectively trapped in the covellite phase, which can exhibit intense, size-tunable LSPR at near-infrared wavelengths despite their stoichiometric, undoped structure. Experimental extinction spectra are satisfactorily reproduced by theoretical calculations performed by the discrete dipole approximation method within the framework of the Drude–Sommerfeld model. The LSPR response of the nanocrystals and its geometry dependence are interpreted as arising from the inherent metallic-like character of covellite, allowed by a significant density of lattice-constitutional valence-band free holes. As a consequence of the unique electronic properties of the nanocrystals and of their monodispersity, coherent excitation of symmetric radial breathing modes is observed for the first time in transient absorption experiments at LSPR wavelengths.
Autore Pugliese
Tutti gli autori
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Y. Xie , L. Carbone , C. Nobile , V. Grillo , S. D'Agostino , F. Della Sala , C. Giannini , D. Altamura , C. Oelsner , C. Kryschi , P. D. Cozzoli
Titolo volume/Rivista
ACS NANO
Anno di pubblicazione
2013
ISSN
1936-0851
ISBN
Non Disponibile
Numero di citazioni Wos
138
Ultimo Aggiornamento Citazioni
28/04/2018
Numero di citazioni Scopus
139
Ultimo Aggiornamento Citazioni
28/04/2018
Settori ERC
Non Disponibile
Codici ASJC
Non Disponibile
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