Luminescent Gold Nanoparticles with Size-Independent Emission.

ABSTRACT: Size-independent emission has been widely observed for ultrasmall thiolated gold nanoparticles (AuNPs) but our understanding of the photoluminescence mechanisms of noble metals on the nanoscale has remained limited. Herein, we report how the emission wavelength of a AuNP and the local binding geometry of a thiolate ligand (glutathione) on the AuNP are correlated, as these AuNPs emit at different wavelengths in spite of their identical size (ca. 2.5 nm). By using circular dichroism, X-ray absorption, and fluorescence spectroscopy, we found that a high Au-S coordination number (CN) and a high surface coverage resulted in strong Au(I) -ligand charge transfer, a chiral conformation, and 600 nm emission, whereas a low Au-S CN and a low surface coverage led to weak charge transfer, an achiral co

SUBMITTER: Liu J 

PROVIDER: S-EPMC5075281 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature