Scanning Tunneling Spectroscopy of Flame-formed Carbon Nanoparticles

In this work, the optoelectronic properties of flame-formed carbon particles at the initial stages of formation and growth was investigated. To this aim, Scanning Tunneling Spectroscopy technique was implemented and applied for the first time to characterize soot particles. Two classes of particles, that can be defined as incipient soot and primary soot particles, have been selectively collected on the basis of their size distribution. Scanning Tunneling Spectroscopy measurements was performed to evaluate the energy band gap and the density of states of flameformed soot nanoparticles and to compare them to those of reference materials, namely coronene and HOPG. The results obtained showed that Scanning Tunneling Spectroscopy is a powerful tool to investigate the optoelectronic properties of nanomaterials, with possible application in combustion science and technology as well as in material science field.