A modification of the polyol-mediated synthesis method was developed to synthesize nanostructured gadolinia-doped ceria. Ce0.9Gd0.1O2-x. The oxide prepared by this method had uniform grains with a size of about 2 nm. The work demonstrated the critical role of water in the synthesis. A yield of up to 81% can be achieved. The as-synthesized Ce0.9Gd0.1O2-x nanoparticles are crystalline with a cubic fluorite type structure. The nanopowders were subsequently consolidated by a modified pulse electric current sintering (PECS) method to produce dense samples with an average size below 16 nm and a relative density of about 96%. The dense material is composed of isolated particles instead of agglomerates and provides an ideal sample for investigation of the size effect on the conductivity. (C) 2010 Elsevier B.V. All rights reserved.