Synthesis of Hollow Black Carbon Nanoparticles by Controlled Oxidation

XIAOFEI MA (1), Joseph M. Conny (2), George W. Mulholland (1), Michael R. Zachariah (1)

(1) University of Maryland-College Park, (2) National Institute of Standards and Technology, Gaithersburg

     Abstract Number: 355
     Last modified: May 10, 2010

Abstract
We report the synthesis of hollow black carbon nanoparticles in the gas phase by a controlled oxidation method. The formation of the hollow black carbon nanostructure was determined by the elemental carbon to organic carbon ratio in the original particles and the oxidation conditions that the particles underwent. The effect of the oxidation conditions on the black carbon nanostructure was examined using transmission electron microscopy. A thermal-optical method was used for measuring the elemental carbon concentration in the particles. For the black carbon particles generated by toluene pyrolysis at 900oC, the elemental carbon to total carbon (EC/TC) ratio was determined to be 1.3%, hollow structures were consistently observed using various oxidizers (O2, CO2, acetone and water) under different oxidation conditions. A mild oxidation condition was necessary for the formation of a hollow structure. For the black carbon particles generated by toluene pyrolysis at 1050oC, EC/TC was about 21.3%, but a hollow structure was not observed.