Shape controlled ZnO nanoparticle prepared by microwave irradiation method

ZnO nanoparticle was successfully prepared by microwave irradiation method in various oxygen/nitrogen ratio atmospheres. In the present method, steel wool was used as a heat generator by microwave irradiation. The highest heating rate of ~200°C/sec for the reaction was achieved under the highest oxygen concentration, 80%, whereas the lowest hating rate was ~40°C/sec. The product prepared in a low oxygen ratio atmosphere showed tetra pod shape with high aspect ratio, c/a. On the other hand, the product prepared under high oxygen ratio atmosphere was relatively isotropic. PL spectra of the products with the higher aspect ratios showed higher UV emission intensity than the products with low aspect ratios i.e. isotropic shape. ©2009 The Ceramic Society of Japan. All rights reserved.