Perovskite Sr2Fe1.5Mo0.5O6-delta (SFM) has been successfully prepared by a microwave-assisted combustion method in air and employed as both anode and cathode in symmetrical solid oxide electrolysis cells (SOECs) for hydrogen production for the first time in this work. Influence of cell operating temperature, absolute humidity (AH) as well as applied direct current (DC) on the impedance of single cells with the configuration of SFM vertical bar La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM)vertical bar SFM has been evaluated. Under open circuit conditions and 60 vol.% AH, the cell polarization resistance, R-P is as low as 0.26 Omega cm(2) at 900 degrees C. An electrolysis current of 0.88 A cm(-2) and a hydrogen production rate as high as 380 mL cm(-2) h have been achieved at 900 degrees C with an electrolysis voltage of 1.3 V and 60 vol.% AH. Further, the cell has demonstrated good stability in the long-term steam electrolysis test. The results showed that the cell electrolysis performance was even better than that of the reported strontium doped lanthanum manganite (LSM) - yttria stabilized zirconia (YSZ)vertical bar YSZ vertical bar Ni-YSZ cell, indicating that SFM could be a very promising electrode material for the practical application of SOEC technology. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.