High-yield synthesis of carbon nano-onions in counterflow diffusion flames

Perylenetetracarboxylic anhydride as a precursor of fluorescent carbon nanoonion rings

“…Similar nanoonions have also been characterised in experiments performing graphite melting at ultrahigh pressure and temperature (5-30 GPa, 5000-6000 ºC), or in flame or by high power laser pulse. [25][26][27] It seems that the thermal treatment in PEG performed here causes an assembling process resulting in analogous nanoobjects, but taking place under our much milder conditions. One of the most interesting properties of C-dots and other carbon nanoforms is the observation for these nanoparticles of an intense photoluminescence.…”

Flame Synthesis of Carbon Nanotubes

“…Counter flow diffusion flames are been increasingly used for synthesis of MWNTs due to their 1-D geometry and convenience in positioning the catalyst substrate in the flame (Hou et al, 2009;Li et al, 2007;Merchan-Merchan et al, 2003;Merchan-Merchan et al, 2004;Merchan-Merchan et al, 2002;Merchan-Merchan et al, 2009;. Merchan-Merchan et al (Merchan-Merchan et al, 2002) recorded the formation of CNTs in a methane oxygen counter diffusion flame without any catalysts.…”

“…Presence of nano-particles and nanotubes inside soot like structure pointed towards a similar mechanism responsible for formation of all three structural forms. Currently, oxy-flames are being pursued for CNT synthesis (Hou et al, 2009;Merchan-Merchan et al, 2009) due to the high temperature and radical concentration obtained at the flame location.…”

Electrochemical Performance of Carbon Onions Fabricated by Electric Arc‐Discharge Method

“…CNOs can be synthesized by a variety of physical and chemical methods, such as arc discharge 6 including arc discharge in water 7, high energy electron irradiation 3, chemical vapor deposition 8, high temperature annealing of nano‐diamond 4, 9, high‐dose carbon ion implantation into metals hydrocarbon in counter flow diffusion flames 10, 11, chlorination of ball milled carbide‐derived carbon 12 and low temperature annealing of metal organic framework 13 etc. Nonetheless, carbon onions obtained so far are varying in core type (single‐nucleus CNOs, multiple‐nuclei CNOs or metal encapsulating CNOs), shape of closure graphitic shells, and shell number 14–16.…”