硼氢化锂(LiBH4)因其高达18.4wt%的含氢量而被用于贮氢材料的研究。但LiBH4放氢和再氢化温度较高,因此如何使其去稳定化(destabilization)从而降低其放氢温度成为研究的热点之一。本文报告了金属硼化物MB2(M=Mg,Ti,Zr)和MB6(M=Ca,La)对LiBH4的去稳定化作用。MB2的添加使LiBH4的放氢温度从450℃降低至350℃,而MB6对LiBH4放氢温度的降低作用更大;而且这些金属硼化物还能有效促进LiBH4放氢后的再氢化反应。XRD,FT-IR,DSC和MS等分析结果表明,金属硼化物在LiBH4的首次放氢过程中起着催化剂的作用,并参与随后的再氢化反应。
In this paper,we report our recent observations of the significant decreases in the dehydrogenation temperature of LiBH4 by the addition of metal borides MB2(M=Mg,Ti,Zr)and MB6(M=Ca,La).MB2 addition reduced the dehydrogenation temperature from about 450℃for pure LiBH4 to 350℃.MB6 demonstrated more significant destabilizing effects on LiBH4.The hydrogen storage reversibility of LiBH4 was also significantly improved due to the presences of the metal borides.The results of XRD,FT-IR,DSC and MS analysis suggest that the metal borides mainly acted as the catalysts for the first dehydrogenation of LiBH4.They participated in the hydrogenation reaction and could be regenerated during the cycling.