Fluorescent carbon nanodots formation in laminar flames

Carbon dots emitting visible fluorescence are the emerging materials which have been recently added to the big family of carbon materials after their discovery in 2004 in arc discharge soot. They are considered as cheaper and health friendly substitutes of inorganic nanostructures currently featuring quantum nanodots. Laser ablation plasma, chemical vapor deposition processes followed by laboratory treatment with oxidation agents are the main sources of carbon dots. Research is currently very active in discovering alternative sources. Combustion in fuel-rich, i.e. pyrolytic, conditions is a known source of strongly fluorescing molecules as polycyclic aromatic hydrocarbons (PAH). In looking for higher molecular weight species and/or particles involved in soot formation, green-fluorescing species have been for the first time detected in the raw soot particles. Thereafter, simple combustion systems like candles have been found as source of carbon nanodots precursors . In view of a possible exploitation of fuel-rich combustion as a convenient and tunable source of quantum carbon nanodots, this work presents insights in the spectroscopic (absorption and fluorescence) properties of fluorescing carbon which accompanies soot formation in laminar flames.