Metal nanoparticle-enhanced radiative transitions: Giving singlet oxygen emission a boost
Artikel i vetenskaplig tidskrift, 2011

The fabrication and use of metal nanoparticles to influence electronic transitions in a given molecule is of growing interest; there is much to be gained by developing and exploiting methods to enhance weak optical signals. Singlet molecular oxygen, O-2(a(1)Delta(g)), which is an important intermediate in many oxidation reactions, particularly in biological systems, is ideally monitored by the 1275-nm O-2(a(1)Delta(g)) -> O-2(X-3 Sigma(-)(g)) phosphorescent transition. Unfortunately, the latter is highly forbidden and, as such, often presents a severe limitation in the application of this optical probe. In this paper, we describe how this weak phosphorescent transition can be enhanced by using localized surface plasmons (LSPs) from specially engineered gold nanostructures. In an attempt to elucidate the mechanism of this process, data were recorded from samples in which we decoupled the component of the plasmon resonance that absorbs incident light from the component that scatters incident light. We find that the latter appears to be the feature of significance in the process through which singlet oxygen phosphorescence is enhanced. In this work, we also illustrate how the singlet oxygen system provides an ideal model for a general study of metal-enhanced radiative rate constants.

singlet oxygen

nanorods

gold nanoparticles

solvent

nanostructures

colloidal lithography

fluorescence intensity

surface

radiative transition

optical-properties

gold nanoparticles

metal-enhanced fluorescence

plasmon resonances

surface plasmon

phosphorescence

Författare

R. Toftegaard

Aarhus Universitet

J. Arnbjerg

Aarhus Universitet

H. P. Cong

Aarhus Universitet

Hossein Agheli

Chalmers, Teknisk fysik, Biologisk fysik

D. S. Sutherland

Aarhus Universitet

P. R. Ogilby

Aarhus Universitet

Pure and Applied Chemistry

0033-4545 (ISSN)

Vol. 83 885-898

Ämneskategorier

Kemi

DOI

10.1351/pac-con-10-09-24