Dehydrogenation and reaction pathway of Perovskite-Type NH4Ca(BH4)3

作者：Lang, Chengguang; Jia, Yi^*; Liu, Jiangwen; Wang, Hui; Ouyang, Liuzhang^*; Zhu, Min; Yao, Xiangdong

来源：Progress in Natural Science, 2018, 28(2): 194-199.

DOI：10.1016/j.pnsc.2018.02.002

• Metal borohydride
• Perovskite
• NH4Ca(BH4)(3)
• Hydrogen storage materials
• Solid-state NMR

Perovskite-type borohydride, NH4Ca(BH4)(3), is considered as a promising hydrogen storage material due to its high gravimetric hydrogen capacity (15.7 wt%). In this work, the dehydrogenation performance and reaction pathway of NH4Ca(BH4)(3) have been systematically investigated. It is found that the initial decomposition temperature is only 65 degrees C, suggesting a low thermodynamic stability of NH4Ca(BH4)(3). The desorption kinetics conducted by differential scanning calorimetry (DSC) indicates that the activation energy of decomposition is about 226.1 kJ/mol. The dehydrogenation pathway of NH4Ca(BH4)(3) characterized by fourier-transform infrared spectroscopy (FTIR) and solid-state nuclear magnetic resonance (NMR) shows a stepwise decomposition process, in which the initial dehydrogenation is due to destabilization of H+ in NH4 and H- in BH4 followed by the subsequent dehydrogenation steps arising from the decomposition of homologous NH3BH3 and the final decomposition of Ca(BH4)(2) at a high temperature, respectively.

• 出版日期2018-4
• 单位华南理工大学