By introducing the inert salt CaF2 as dispersant, a convenient low-temperature method has been developed and gallium nitride nanowires have been successfully synthesized on Si substrate through the direct nitridation of Ga-CaF2 mixture in NH3/N-2 at 650 degrees C, about 250 degrees C lower than those in literature reports. This preparation method is also applicable to effectively decrease the synthesis temperature of some other nanostructures of the low-melting-point-metal oxides or nitrides such as Ga2O3, SnO2, In2O3 and AIN. (C) 2008 Elsevier B.V. All rights reserved.