Morphology of supported silver nanoparticles characterized by optical and thermal desorption spectroscopy

Silver nanoparticles grown on a quartz substrate are investigated with optical and thermal desorption spectroscopy (TDS). Detailed information on the nanoparticle morphology is gained with new methods of data analysis. First, fitting the extinction spectra, using a comprehensive model, allows an estimation of the effective particle-particle distance. Second, the total surface area of the particles is determined with TDS of xenon. Third, the dependence of the plasmon resonance position on the amount of adsorbed xenon or benzene is used as a measure of the average particle size. The results for these three parameters, which are critical for potential applications of nanoparticle arrays, are shown to be mutually consistent. The methods demonstrated here are complementary to scanning probe techniques which characterize the particle morphology on a microscopic length scale.