We report a rapid and cost-effective method to coat SDC nano-particles with a thin LiZn-oxide nanocomposite layer. This composite is determined to have a structure with two phases consisting of Li2O and ZnO and examined to distribute over the surfaces of SDC nano-particles uniformly by using energy dispersive X-ray (EDX) and high-resolution TEM (HRTEM). The measurments of electrical property demonstrate that such a thin layer enables the ionic conductivity of SDC to be significantly increased (higher than 0.1 S cm(-1) at the temperature of 300 degrees C) equivalent to the conductivity of pure SDC at 800 degrees C or YSZ at 1000 degrees C. This superionic conductivity is caused by the two-phase interfaces formed between nano-particles. (C) 2011 Elsevier B.V. All rights reserved.