Microwave-induced hydrogen production at medium temperature of iron oxide/hercynite composite

This research investigates the impact of different iron phases on the reduction and oxidation steps of an iron composite for hydrogen production application. A conventional heating route and a microwave technology are employed for thermochemical water splitting to compare the effect of a mixture of iron phases and heating mode in the reduction and reoxidation steps. In this work, the use of microwave technology, is reported for the first time for iron oxide/hercynite materials. This activation route is presented as an alternative to decrease both the high reduction and oxidation temperatures (1400 and 1000 degrees C, respectively) usually required for these materials. H2 generation is confirmed at reoxidation temperature of only 478 degrees C, which is significantly lower than those reported in literature (>= 1000 degrees C). The results confirm that the presence of FeO phase after the reduction step in the microwave, plays a key role in the reoxidation process and therefore in the H2 production, with amounts of 11 mu mol/g. These findings emphasize the importance of deeply studying redox-active materials which may be susceptible to reduction and reoxidation processes using microwave technology.