Abstract

The effects of oxidation on the hydrogen release behavior of magnesium borohydride and calcium borohydride were investigated using differential scanning calorimetry. To date, studies on the oxidation kinetics of borohydride compounds in air and the influence of oxidation on hydrogen desorption behavior have been limited. In this work, the degree of oxidation and the corresponding changes in hydrogen release temperature were analyzed based on DSC signals to evaluate the extent of oxidation and its effect on hydrogen desorption characteristics. In addition, the influence of ScCl3, a commonly used metal catalyst, on the oxidation behavior of borohydrides was also examined. Both compounds were found to undergo complete oxidation within one day; however, the oxidation-induced changes in hydrogen release temperature were minimal. The addition of the ScCl3 catalyst did not induce significant changes in the oxidation process, but slightly reduced the oxidation rate and led to the formation of additional intermediate phases. Further in-depth studies are required to elucidate the mechanisms underlying these phenomena.