Pyrolytic decomposition of aqueous zinc nitrate for crystalline ZnO nanobeads architecture oriented along (002) plane with hexagonal crystal structure is presented as a concentration of aqueous zinc nitrate solution. As-observed ZnO nanobeads were used for surface morphological, optical and electrical properties. Decrease in zinc nitrate concentration results in the destruction of the foggy-like morphology with newly formed dense nanograins and finally, porous nanobeads. The optical absorption studies revealed that the ZnO nanobeads exhibit the optical band gap of 3.30eV. However, an increase in electrical resistivity with decrease in concentration of zinc nitrate solution was observed. (c) 2006 Elsevier B.V. All rights reserved.