The growth of TiO2 nanorods on a WC-Co substrate by metalorganic chemical vapor deposition has been observed by SEM and TEM. The nanorods diameter and length were about 50-100 nm and 0.5-2 mum, respectively. Nanorod growth was observed at 500degreesC, while mostly particles were deposited at 600degreesC and a thin coating was formed at 400degreesC. It appears that the presence of cobalt catalyzes the directional growth of TiO2 and NH3 enhances this growth behavior. In the presence of NH3, thinner and longer nanorod growth was observed. (C) 2003 Elsevier B.V. All rights reserved.