High-quality nano-sized Ce0.8Dy0.2O2-delta powders were synthesized by the solution combustion method, using C4H7NO4 (aspartic acid) as the combustion fuel. The nano-sized Ce0.8Dy0.2O2-delta powders provided an ultra-fine grain size and high density even at low sintering temperatures (1250-1400 degrees C), engendering high electrical conductivity. The magnitude of electrical conductivity depended strongly on the sintering temperature and followed the order of 1350 degrees C > 1300 degrees C > 1250 degrees C > 1400 degrees C. The electrical conductivity of the Ce0.8Dy0.2O2-delta sintered at 1350 degrees C was 0.206 S cm(-1) at 800 degrees C. The high electrical conductivity can lower operating temperature of solid oxide fuel cells. We demonstrate that synthesizing nano-sized powders and controlling grain size are important for enhanced Ce0.8Dy0.2O2-delta electrolytes. (C) 2013 Elsevier Ltd. All rights reserved.