We have developed a high-performance cathode for solid oxide electrolysis cells (SOECs) for hydrogen production. Mixed conducting samaria-doped ceria (SDC) particles were employed in combination with highly dispersed Ni electrocatalysts. The Ni (8 vol %) dispersed SDC cathode exhibited very high performance at a water vapor pressure >0.4 atm at 900 degrees C. An SOEC, comprised of Ni-dispersed SDC cathode, La(Sr) CoO3 anode with SDC interlayer, and YSZ electrolyte, exhibited fairly high performance; IR-free cell voltage = 1.20 V at 0.50 A cm(-2) and 900 degrees C under the atmosphere of H-2 + H2O (p[H-2] = 0.6 atm, p[H2O] = 0.4 atm), and O-2 (1 atm). (C) 2004 The Electrochemical Society.