Materials designing of metal borohydrides: Viewpoints from thermodynamical stabilities
Materials designing of metal borohydrides: Viewpoints from thermodynamical stabilities
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DOI：
10.1016/j.jallcom.2007.02.156
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发表时间：
2007-10
影响因子：
6.2
通讯作者：
Haiwen Li;S. Orimo;Y. Nakamori;K. Miwa;N. Ohba;S. Towata;A. Züttel
中科院分区：
文献类型：
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作者：
Haiwen Li;S. Orimo;Y. Nakamori;K. Miwa;N. Ohba;S. Towata;A. Züttel
合成了双阳离子硼氢化物MLim-n（BH_4）_m（M=Zn，n=2; M=Al，n=3; M=Zr，n=4; n≤m），并对其稳定性进行了实验研究。ZnLi（BH_4）_3和AlLi（BH_4）_4的样品在加热时分别发生Zn（BH_4）_2-（或Al（BH_4）_3-）和LiBH_4基相的歧化反应。然而，在ZrLim−4（BH 4）m（m=5和6）中没有观察到反硝化反应。需要强调的是，ZrLim−4（BH 4）m的氢脱附温度Td随着组成m从4增加到6而从440 K连续增加到650 K，并且接近740 K（LiBH 4的Td）。实验结果表明，与传统的贮氢合金“合金化”方法类似，适当的阳离子组合是调节金属硼化物的热稳定性的有效方法。
Double-cation borohydrides MLim−n(BH4)m(M=Zn, n=2; M=Al, n=3; M=Zr, n=4; n≤m) were expected to be synthesized and their thermodynamical stabilities were also examined experimentally. The samples with the compositions of ZnLi(BH4)3and AlLi(BH4)4disproportionate into Zn(BH4)2- (or Al(BH4)3-) and LiBH4-based phases upon heating, respectively. However, no disproportionation reaction is observed in ZrLim−4(BH4)m(m=5 and 6). It should be emphasized that hydrogen desorption temperature Tdof ZrLim−4(BH4)mcontinuously increases from 440 to 650K as the composition m increases from 4 to 6, and approaches to 740K (Tdof LiBH4). The experimental results indicate that the combination of appropriate cations is an effective method to adjust the thermodynamical stabilities of metal borohydrides, similar to the conventional “alloying” method for hydrogen storage alloys.