In this paper, we describe a one-step and solution (water-based) synthesis method for preparing rutile nano-ellipsoids by heating the peroxotitanium complex precursor at 100 degrees C. The size of the nanoellipsoids could be controlled by changing precursor concentration. Transmission electron microscopy (TEM) results show that the particles have different length-width ratio depending on the system acidity. The crystal growth mainly follows the oriented attachment process. The resulting samples are also characterized with UV-vis absorption and diffuse reflectance spectra. The smaller particles exhibited higher photocatalytic activity as evaluated in the degradation of methylene blue. (C) 2010 Elsevier B.V. All rights reserved.