The purpose of this study is to investigate an innovative nanorod preparation method, the submerged arc nanoparticle synthesis system. The key parameters such as discharge current, breakdown voltage, pulse duration, and temperature of the dielectric liquid are carefully analyzed in order to obtain more uniform nanorods. The prepared nanorods were systematically characterized by x-ray diffraction, transmission electron microscopy, selected-area electron diffraction, x-ray photoelectron spectroscopy, and the ultraviolet-visible absorption spectrum. The results showed that the CuO nanorods had a diameter of 30-50 nm and a longitudinal length of up to 1-2 mu m. A possible preparation mechanism was also discussed for the growth of the CuO nanorods. (c) 2005 American Vacuum Society.