The Sm doped CeO2 powder material prepared with sol and gel,is sintered with Spark-plasma sintering(SPS) and conventional sintered(CS) respectively to compare the differences of the two methods.The structures and ionic conductivities are characterized with X-ray Diffraction(XRD),field-emission scanning electron microscopy(FE-SEM) and electrochemical impedance spectroscopy(EIS).The results show that all the materials are single-phase with a cubic fluorite structure;the grain size and density of the SPS sampl...