Microtubular complex precursors were grown via a hydrothermal route using ZnCl2 or CdCI2 and sulfur at 120 degrees C for 12-24 h. The tubular complexes precursors were composed of S2- and Zn2+ or Cd2+ ions and ethylenediamine (en) molecules. Microtubes consisted of nanocrystalline ZnS and US were obtained by annealing the precursors in nitrogen stream at 400 degrees C. The as-prepared precursors and annealed products were characterized by powder X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, inductively coupled plasma atomic emission spectrometry and combustion for C, N, H contents. The formation mechanism of microtubes is discussed. The synthesized precursors could be used as morphological templates to prepare nanostructure inorganic compounds. (c) 2006 Elsevier B.V. All rights reserved.