Nanoparticle of TiO2 co-doped with Sc3+ and V5+ ions was synthesized by the sol-gel method and calcinated at 500 degrees C. Particle size of TiO2 + 2.0 at.% (Se + V) calculated from XRD spectrum is 16.2 nm. The size and shape of nanoparticles synthesized were also obtained by transmission electron microscopy (TEM) and mean diameter of particle was determined as 17.4 +/- 5.4 nm, which is in agreement with that of calculated from XRD spectrum. Image from high-resolution transmission electron microscopy (HRTEM) study on the sample exhibited well-defined lattice fringe. Elemental analysis was conducted by energy-dispersive Xray microanalysis (EDX) and confirmed the presence of Sc3+ and V5+ ions in the TiO2 matrix. (c) 2005 Elsevier B.V. All rights reserved.