Calcium borohydride for hydrogen storage: catalysis and reversibility.

摘要: We demonstrate a new solid-state synthesis route to prepare calcium borohydride, Ca(BH4)2, by reacting ball-milled mixture of CaB6 and CaH2 in molar ratio 1:2 at 700 bar H2 pressure 400−440 °C. Moreover, doping with catalysts was found be crucial enhance reaction kinetics. Thermogravimetric analysis differential scanning calorimetry revealed reversible low-temperature high-temperature endothermic phase transition 140 °C another 350−390 associated hydrogen release upon formation CaH2, as evident from X-ray diffraction analysis. Thus, since Ca(BH4)2 here is shown prepared its anticipated decomposition products, the conclusion that it has potential utilized storage material. The theoretical capacity 9.6 wt % hydrogen.