Steven Rogak
The University of British Colombia, Canada
Title: Aerosol carbon nanoparticles: The connection between aggregate morphology and nano-structural features
Biography
Biography: Steven Rogak
Abstract
Aerosol nanoparticles composed mainly of carbon are created unintentionally from fuel-rich non-premixed combustion; this “soot” or “black carbon” has enormous climate and health implications. “Carbon black”, however, is created intentionally as a material filler or pigment, and exhibits nearly the same structure: fractal-like aggregates of nearly-spherical primary particles.
Recently our group has found that the primary particles within soot aggregates from a combustion source have a wide size range (8-80 nm), but the distribution within individual aggregates is quite narrow, and generally larger aggregates have larger primary particles. This suggests that the aggregate morphology is derived from highly localized conditions within flames.
Carbon aerosol particles segregated by physical characteristics (aerodynamic size or mass) have different optical properties and show different Raman spectra. This might be of interest in tuning material properties, but it is also of fundamental interest to combustion researchers because it means that particle morphology carries with it information on the distribution of soot formation conditions in flames.