Particle Size Dependence of Flame-Synthesized Carbon Nanostructures on the Flow Rates of Fuel and Oxidizer

Abstract

Aggregates of spherical carbon nanostructures were grown directly on stainless steel substrate in a controllable co-flow diffusion flame. The flow rates of fuel and oxidizer were found to have a key influence on the size of the synthesized particles. At fuel to oxidizer flow rate ratio of 0.7, carbon nanostructures with diameter range of 24–46[Formula: see text]nm were obtained. However, the diameter was reduced to 6–15[Formula: see text]nm as we decrease the flow rate ratio to 0.14. Apart from decrease in crystallite and particle size revealed by XRD spectra and HRTEM images, respectively, the Raman spectra showed the decrease in disorder-induced features at lower flow rate ratio.