Synthesis and hydrolysis of NaZn(BH4)(3) and its ammoniates
Synthesis and hydrolysis of NaZn(BH4)(3) and its ammoniates
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NaZn(BH4)(3)及其氨化物的合成与水解
DOI：
10.1039/c7ta05082h
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发表时间：
2017
影响因子：
11.9
通讯作者：
M. Zhu
中科院分区：
文献类型：
--
作者：
M. C. Wang;L. Z. Ouyang;C. H. Peng X. K. Zhu;W. H. Zhu H. Y. Shao;M. Zhu
研究了NaZn(BH4)3及其氨化物的合成及其水解性能。通过x射线衍射和傅里叶变换红外光谱测量证实了NaZn(BH4)3及其氨化物的成功合成。水解结果表明，NaZn(BH4)3能够在5分钟内生成1740 mL g−1氢气，在30分钟内生成1956 mL g−1氢气，而不会同时释放氨或硼烷等不良气体。在一些产氢的情况下，这个速率可能太快而无法控制。此外，还发现NaZn(BH4)3·2NH3在5 min内生成118ml g−1氢气，在2 h内生成992ml g−1氢气，并伴有少量氨的排放。此外，通过形成NaZn(BH4)3/NaZn(BH4)3·2NH3复合材料可以提高水解性能。通过行星球磨技术合成的复合材料可以以非常合理可控的速度生成氢气，分别为5min 717 mL g−1氢气和2h 1643 mL g−1氢气。计算出NaZn(BH4)3、NaZn(BH4)3·2NH3和NaZn(BH4)3/NaZn(BH4)3·2NH3复合材料在去离子水中的水解活化能分别为11.9 kJ mol−1、56.9 kJ mol−1和32.5 kJ mol−1。上述结果表明，无催化剂的NaZn(BH4)3及其氨化物比其他NaBH4基材料具有更好的水解动力学，具有作为固体制氢材料的潜力。
The synthesis and hydrolysis performance of NaZn(BH4)3 and its ammoniates were investigated in this paper. The successful synthesis of NaZn(BH4)3 and its ammoniates was confirmed by X-ray diffractometry and Fourier transform infrared spectroscopy measurements. The hydrolysis results show that NaZn(BH4)3 is able to generate 1740 mL g−1 hydrogen in 5 min and 1956 mL g−1 hydrogen in 30 min without concomitant release of undesirable gases such as ammonia or boranes. This rate can be too fast to be controllable in some hydrogen generation cases. In addition, it is found that NaZn(BH4)3·2NH3 generates 118 mL g−1 hydrogen in 5 min and 992 mL g−1 hydrogen in 2 h, accompanied by an emission of a small amount of ammonia. Furthermore, an enhanced hydrolysis performance can be achieved by formation of NaZn(BH4)3/NaZn(BH4)3·2NH3 composites. These composites synthesized via a planetary ball milling technique may generate hydrogen with a very reasonable and controllable speed of 717 mL g−1 hydrogen in 5 min and 1643 mL g−1 hydrogen in 2 h. The activation energies for the hydrolysis in deionized water of NaZn(BH4)3, NaZn(BH4)3·2NH3 and the NaZn(BH4)3/NaZn(BH4)3·2NH3 composite milled for 30 min were calculated to be 11.9 kJ mol−1, 56.9 kJ mol−1 and 32.5 kJ mol−1, respectively. These results demonstrate that the catalyst-free NaZn(BH4)3 and its ammoniates show better hydrolysis kinetics than other NaBH4 based materials and have the potential to be used as solid hydrogen generation materials.