Ultrafine fluorite type Dy2Zr2O7 nanocrystals with cubic structure were fabricated at relatively low temperature by stearic acid method (SAM) using zirconium(IV) butoxide and dysprosium nitrate as raw materials, stearic acid as solvent and dispersant. The fabrication process was monitored by thermogravimetric analysis and differential thermal analysis (TG-DTA) and Fourier transform infrared spectroscopy (FT-IR). The obtained products were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive Xray spectrometer (EDS) and UV-vis absorption spectroscopy. A single phase of Dy2Zr2O7 with high crystallinity was formed at 800 degrees C. The interplanar distances measured from the HRTEM image were 0.284 and 0.256 nm, respectively, coinciding with the theoretical values. (C) 2007 Elsevier Ltd. All rights reserved.