Raman Spectroscopy of Nascent Soot Oxidation: Structural Analysis During Heating

The effect of oxidation on nascent soot particles is investigated in this work by means Raman spectroscopy. Three different particle samples are produced a lightly sooting ethylene/air laminar premixed flame and collected at residence times. characterized size primary degree aging hence graphitization, they representative the early evolution flames. Oxidation induced exposing to high temperature treatment air over range 25–500°C. To aim, programmable heating microscope stage used. Thermo-optical transmission (TOT) measurements used characterize chemical composition pristine terms organic elemental carbon content, also providing pyrolytic fraction carbon. TOT results show that constant for three conditions. On other hand, decreases increases when moving from sample composed just-nucleated mostly made mature particles. spectroscopy reveals thermal performed particles, with highest reduction amorphous component. Conversely, soot, shows an increase phase after oxidation, which attributed fragmentation or formation point defects O 2 oxidation. Finally, procedure produces strong photoluminescence signal detected spectra.