A method is proposed to estimate the size distribution of nearly spherical metallic nanoparticles (NPs) from optical extinction spectroscopy (OES) measurements based on Mie’s theory and an optimization algorithm. The described method is compared against two of the most widely used techniques for the task: transmission electron microscopy (TEM) and small-angle x-ray scattering (SAXS). The size distribution of Au and Cu NPs, obtained by ion implantation in silica and a subsequent thermal annealing in air, was determined by TEM, grazing-incidence SAXS (GISAXS) geometry, and our method, and the average radius obtained by all the three techniques was almost the same for the two studied metals. Concerning the radius dispersion (RD), OES and GISAXS give very similar results, while TEM considerably underestimates the RD of the distribution.
© 2009 Optical Society of America
Original Manuscript: November 14, 2008
Revised Manuscript: December 17, 2008
Manuscript Accepted: December 19, 2008
Published: January 15, 2009
Ovidio Peña, Luis Rodríguez-Fernández, Vladimir Rodríguez-Iglesias, Guinther Kellermann, Alejandro Crespo-Sosa, Juan Carlos Cheang-Wong, Héctor Gabriel Silva-Pereyra, Jesús Arenas-Alatorre, and Alicia Oliver, "Determination of the size distribution of metallic nanoparticles by optical extinction spectroscopy," Appl. Opt. 48, 566-572 (2009)