MgO nanobelts with a pure morphology and high yield were generated by the direct evaporation of Mg metals under initial N-2 gas at 650 degreesC and subsequent N-2/O-2 atmosphere at 800 degreesC. The growth of these MgO nanobelts is explained in a VS route in which the in situ formed Mg3N2 slowly decomposes and reacts with oxygen. Mg3N2 is therefore a very effective precursor for the fabrication of high-purity one-dimensional (1D) MgO nanostructures. (C) 2003 Elsevier Science B.V. All rights reserved.