Anode-supported microtubular SOFCs based on ceria 3 +/- 0.2 mm diameter and about 100 mm in length have been prepared using gadolinia-doped ceria (GDC) nanopowders. Nanometric Ce(0.9)GD(0.1)O(1.95) (GDC) powders were deposited on NiO-Ce0.9Gd0.1O1.95 (NiO-GDC) anode supports by dip-coating techique. Fabrication conditions to obtain dense and gas tight electrolyte layers on porous microtubular supports were studied. Three different dispersing agents: commercial Beycostat C213 (CECA, France) and short chain monomer (<= 4 carbon atoms) with alcohol or carboxylic acid functional groups were evaluated. By optimizing colloidal dispersion parameters and sintering process gas tight and dense GDC layers were obtained. Significantly lower sintering temperatures than reported previously (<= 1300 degrees C) were employed to reach >= 98% values of theoretical density within electrolyte layers of similar to 10 mu m in thickness. A composite cathode. LSCF-GDC 50wt% with about 50 mu m thickness was dip coated on the co-fired half-cell and then sintered at 1050 degrees C for 1 h. The electrochemical performance of these cells has been tested. In spite of electronic conduction due to partial reduction of the thin-electrolyte layer, the I-V measurements show power densities of 66mWcm(-2) at 0.45V at temperatures as low as 450 degrees C (using 100% H-2 as fuel in the anodic campartment and air in the cathodic chamber). (C) 2010 Elsevier B.V. All rights reserved.