The asymmetric alpha-Si(3)N(4) nanocombs have been prepared by direct current arc discharge method without the addition of any catalyst or template. The nanocombs are composed of closely packed Si(3)N(4) nanowires, which grow perpendicular to the central axial nanorods in an epitaxial manner. The growth mechanism of the alpha-Si(3)N(4) nanocombs can be considered as a combination of the vapor solid mechanism and the secondary epitaxial nucleation process. The photoluminescence spectra of the nanocombs show a strong blue light emission peak at about 424 nm. (C) 2010 Elsevier Ltd. All rights reserved.