Luminescent hollow carbon shells and fullerene-like carbon spheres produced by laser ablation with toluene

Hollow carbon shells and fullerene-like carbon spheres are prepared by laser ablation with toluene molecules as a carbon precursor. The liquid carbon precursor is superior to the gaseous carbon precursors conventionally used, such as C2H2, due to its safety and ease of handling. The formation mechanism of these carbon nanostructures is discussed. The laser irradiation-induced high temperature results in the decomposition of toluene molecules to carbon atoms. Consequently, these carbon atoms nucleate and grow to novel carbon nanostructures as the temperature drops. The graphene-like hollow carbon shells show strong and excitation wavelength-dependent light emission, which has potential optical applications.