ONE-POT SYNTHESIS OF CARBON NANOPARTICLES, NANOCAGES OR GRAPHENE BY LASER IRRADIATION IN LIQUID

摘要

A variety of carbon nanostructures, such as fullerenes, carbon nanotubes, carbon nanocagesfl], grapheme[2], and surface-passivated carbonaceous quantum dots (so-called carbon dots)[3], are inspiring intensive research efforts in its own right. These nanocarbons show great potential in various fields owing to their unique physical properties. Therefore, a facile, green, cheap and versatile synthetic approach for them is highly desired. Pulsed laser ablation in liquid (PLAL) has been of interest as a green, cheap, facile and versatile approach for the synthesis of various nanostructures in recent years. Comparing with the nanostructures obtained upon PLAL, the soild material (or target) employed previously in the experiment has a relatively large volume. The total quantity of the obtained nanostructures is only a small fraction of the original solid material. However, if we reduce the size of the solid material and control the laser beam energy, a large proporition of the solid material is etched away and only a less part is left. The etched part will enter into the laser-induced bubble and then forms the new nanostructures by condension nucleation and chemical reaction. Conceivably, if the size is small enough, the left part become a nanomaterial with the original material structure, or form a new nanostructure under laser energy induction. Thus, two absolutely different nanostructures could be simultaneously synthesized by the PLAL method. According to above consideration, we present a novel approach to one-pot synthesis of carbon dots and carbon nanocages, or carbon dots and graphene nanoplatelets by controlling laser power density (LPD), and the size and kind of carbon source in the polymer solution. To the best of our knowledge, so far no one has reported similar work.