Graphite electrodes were used for the direct current (DC) arc discharge in wa-ter.And high-resolution transmission electron microscopy (HRTEM) was used to investigate theproducts.Based on the experimental phenomena and nano-structure products,arc plasma char-acteristics in water were analyzed theoretically.Two growth regions and relevant growth modeswere proposed to interpret the formation mechanisms of nano-structures by arc discharge in wa-ter.Furthermore,liquid nitrogen and cross magnetic field was applied to change the arcing staterespectively,and new carbon nano-structures were obtained.Their formation mechanisms werealso analyzed correspondingly.
