The iron oxide and Mo-modified iron oxide samples, which can store and produce pure hydrogen by the redox reaction (Fe3O4 (initial Fe2O3) + 4H(2) <-> 3Fe + 4H(2)O), were prepared via hydrothermal method. The redox performances of all samples were investigated, of which Fe2O3-7.5%Mo-a displayed the best one on enhancing hydrogen production. E.g., the average temperature of H-2 formation was only 277 degrees C; H-2 formation rate at 300 degrees C was 581-915 mu mol min(-1) Fe-g(-1) from the first to fourth redox cycles; the average storage capacity was up to 4.7 wt% in four redox cycles. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.