title: Determination of the size distribution of metallic nanoparticles by optical extinction spectroscopy.
abstract: 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.
authors.affiliation: Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, Coyoacan, C.P. 04510, México, DF, México. ovidio@bytesfall.com
authors.forename: Ovidio
authors.initials: O
authors.lastname: Peña
authors.forename: Luis
authors.initials: L
authors.lastname: Rodríguez-Fernández
authors.forename: Vladimir
authors.initials: V
authors.lastname: Rodríguez-Iglesias
authors.forename: Guinther
authors.initials: G
authors.lastname: Kellermann
authors.forename: Alejandro
authors.initials: A
authors.lastname: Crespo-Sosa
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Cheang-Wong
authors.forename: Héctor Gabriel
authors.initials: HG
authors.lastname: Silva-Pereyra
authors.forename: Jesús
authors.initials: J
authors.lastname: Arenas-Alatorre
authors.forename: Alicia
authors.initials: A
authors.lastname: Oliver
mesh_terms: D000465:Algorithms; D003300:Copper / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000032:analysis / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D015233:Models, Statistical; D036103:Nanotechnology / Q000379:methods*; D016011:Normal Distribution; D055095:Optics and Photonics; D012542:Scattering, Radiation; D013057:Spectrum Analysis / Q000379:methods*; D055672:Static Electricity; D014965:X-Rays
chemical_list: D006046:Gold; D003300:Copper