A catalyst-free and highly efficient synthetic method for growing carbon nano-onions (CNOs) in open air has been developed through the laser resonant excitation of a precursor molecule, ethylene, in a combustion process. Highly concentric CNO particles with improved crystallinity were obtained at a laser wavelength of 10.532νm through the resonant excitation of the CH2 wagging mode of the ethylene molecules. A higher growth rate up to 2.1gh - 1 was obtained, compared with that without a laser (1.3gh - 1). Formation of the CNOs with ordered graphitic shells is ascribed to the decomposition of polycyclic aromatic hydrocarbons (PAHs) into C 2 species. The optical limiting performances of the CNOs grown by the combustion processes were investigated. CNOs grown at 10.532νm laser excitation demonstrated improved optical limiting properties due to the improved crystallinity.
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering