Photoactivated Fluorescence from Individual Silver Nanoclusters
Lynn A. Peyser,
Amy E. Vinson,
Andrew P. Bartko,
Robert M. Dickson*
Fluorescence microscopy of nanoscale silver oxide
(Ag2O) reveals strong photoactivated emission for
excitation wavelengths shorter than 520 nanometers. Although blinking
and characteristic emission patterns demonstrate single-nanoparticle
observation, large-scale dynamic color changes were also observed, even
from the same nanoparticle. Identical behavior was observed in oxidized thin silver films that enable Ag2O particles to grow at
high density from silver islands. Data were readily written to these
films with blue excitation; stored data could be nondestructively read with the strong red fluorescence resulting from green (wavelengths longer than 520 nanometers) excitation. The individual luminescent species are thought to be silver nanoclusters that are photochemically generated from the oxide.
School of Chemistry and Biochemistry, Georgia Institute of
Technology, Atlanta, GA 30332-0400, USA.
*
To whom correspondence should be addressed. E-mail:
dickson{at}chemistry.gatech.edu
