Voltage-induced adsorbate damping of single gold nanorod plasmons in aqueous solution.
Unbiased gold nanoparticles are negatively charged in aqueous solution but not hydrated. Optical spectroscopy of voltage-clamped single gold nanoparticles reveals evidence that anion adsorption starts at positive potentials above the point of zero charge, causing severe but reversible plasmon damping in combination with a spectral red shift exceeding the linear double layer charging effect. Plasmon damping by adsorbate is relevant for the use of nanoparticles in catalysis, in biodiagnostics, and in surface enhanced Raman scattering.
Photonics and Optoelectronics Group and CeNS, Department of Physics, Ludwig-Maximilians Universität München, 80799 München, Germany.
S K
SK
Dondapati
M
M
Ludemann
R
R
Müller
S
S
Schwieger
A
A
Schwemer
B
B
Händel
D
D
Kwiatkowski
M
M
Djiango
E
E
Runge
T A
TA
Klar
D000327:Adsorption / Q000528:radiation effects; D004574:Electromagnetic Fields; D006046:Gold / Q000737:chemistry* / Q000528:radiation effects; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects*; D012996:Solutions; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties / Q000528:radiation effects; D014867:Water / Q000737:chemistry*
D012996:Solutions; D014867:Water; D006046:Gold