Modification of excimer emission of perylene dye thin films by single silver nanocubes

Modification of the excimer emission of N,N′-bis(2,5-di-tert-butylphenyl)-3,4,9,10-perylene dicarboximide (PDI) by localized surface plasmon resonance (LSPR) of silver nanocubes (SNCs) 100–170 nm in size was investigated by single-particle spectroscopy. SNCs were immobilized on a glass substrate and then covered with a 20-nm-thick PDI film via vacuum vapor deposition. Using fluorescence microscopy to compare areas with and without single SNCs on the same sample, we demonstrated the enhanced intensity and modulated spectral shape of the excimer emission by single SNCs. The excimer emission modification was examined for various sizes of SNCs and different LSPR peak positions, and the electromagnetic field enhancement effect on the radiation emission process was discussed.

► The fluorescence enhancement by silver nanocubes studied by single particle spectroscopy.
► The modulation of the emission spectral shape by the local surface plasmon resonance is demonstrated.
► The modified emission peak wavelength increases with the peak position of the local surface plasmon resonance band.
► The result will evidence the electromagnetic field enhancement of the radiative transition rate of fluorescence.