Hydrogen storage and release properties of a Cu-added Fe/YSZ redox system

Abstract

Hydrogen storage and release by the redox reaction of an iron oxide with yttria-stabilized zirconia (YSZ) were investigated. YSZ was introduced to the samples to improve the thermal stability of the iron oxide. The average size of the samples synthesized using urea was 40-50 nm, whereas those synthesized using Na2CO3 as a precipitant were 150-200 nm. The sample prepared via coprecipitation using urea exhibited better stability than the other samples. We prepared the Cu-added Fe/YSZ sample to enhance the low-temperature reactivity. The water-splitting reaction was initiated at approximately 200°C, and the maximum rate of hydrogen evolution was observed at approximately 350°C. In the isothermal redox test over 35 cycles, the degree of hydrogen storage and release was almost maintained over 1.8 wt% based on the total amount of the sample. © 2013 Hyo-Sub Kim et al.