Rapid synthesis and structure control of carbon spheres by ultrasound method

The rapid synthesis (within five minutes) of truly monodispersed carbon spheres (CS) using an ultrasonic method was consistantly maintained by systematically optimizing various experimental parameters (e.g. catalyst concentration, solvent composition, ultrasonic power, ultrasonic time, reaction temperature, and precursor concentration). Uniform nitrogen doped carbon spheres (N-CS) are for the first time successfully fabricated by ultrasonic method using resorcinol and formaldehyde as carbon precursors, melamine as nitrogen source. The effect of fabrication parameters on the morphology and structure of the spheres was systematically investigated. The diameters of the N-CS are successfully tuned from nano-scale to submicro-scale (40-1000 nm) by varying the catalyst concentration. In general, the diameter of the N-CS decreases with increasing the concentration of the catalyst. The surface area and pore volume of the N-doped CS before activation were up to 642.0 m2/g and 0.834 m3/g, respectively. The possibility of activation of N-CS using phosphoric acid(H3PO4) was subsequently studied in here. Modified porous CS was successfully synthesized using resorcinol and formaldehyde as carbon precursor and silica nano-particles as template. Morphology and structure of the Si-template modified CS were also studied in this work