The low-loss EELS spectra from radiation damaged gold nanoparticles

Abstract

The advantage of the EELS spectra in transmission electron microscopy is the ability to obtain plasmon information of the structure of individual nanoparticles. The EELS analyses of the plasmonic information of gold nanoparticles were obtained before and after irradiation by the convergent beam electron diffraction (CBED) technique. The results indicate that before irradiating the gold nanoparticles (35 nm in diameter) by the CBED technique, only the EELS spectrum of carbon is obtained. Nevertheless, the EELS spectra of gold were obtained after CBED irradiation of the nanoparticles. The spectrum of gold shows five plasmonic modes at 15.9, 24.8, 32.8, 45.4, and 63.2 eV, but theoretical surface and bulk plasmons of gold are at 6.378 and 9.020, respectively. When compared with the experimental plasmon peaks, we determined that peaks at energies above 9.026 eV are multiples of the surface and bulk (valence) plasmons of the gold nanoparticles.