Ammonia borane modified zirconium borohydride octaammoniate with enhanced dehydrogenation properties

A new complex system, Zr(BH4)(4)center dot 8NH(3)-nNH(3)BH(3) (n = 2, 3, 4, 5), was prepared via ball milling of Zr(BH4)(4)center dot 8NH(3) and NH3BH3 (AB). The combination strategy effectively suppressed ammonia release and reduced the dehydrogenation temperature when compared to the individual compounds. In the optimized composition, Zr(BH4)(4)center dot 8NH(3)-4AB, the hydrogen purity was improved to 96.1 mol% and 7.0 wt% of hydrogen was released at 100 degrees C. These remarkable improvements are attributed to the interaction between AB and the NH3 group in Zr(BH4)(4)center dot 8NH(3), which enables a more active interaction of H delta+center dot center dot center dot H-delta. These advanced dehydrogenation properties suggest that Zr(BH4)(4)center dot 8NH(3)-4AB is a promising candidate for potential hydrogen storage applications.