Fullerenic nanostructures in flames

High resolution transmission electron microscopy (HRTEM) was used to characterize nanostructures in soots produced in flames of benzene, acetylene, or ethylene premixed with oxygen and an inert diluent gas. The nanostructures ranged from ∼2 nm to ∼30 nm in size with a hollow core measuring about ∼ 1 nm to ∼10 nm in diameter and containing 5 to 20 shells. The shapes of the nanostructures included spherical, spheroidal, tubular, and trigonous.