Ammonia borane-metal alanate composites: hydrogen desorption properties and decomposition processes

作者：Nakagawa Yuki; Ikarashi Yudai; Isobe Shigehito^*; Hino Satoshi; Ohnuki Somei

来源：RSC Advances, 2014, 4(40): 20626-20631.

DOI：10.1039/c4ra02476a

Hydrogen desorption properties and decomposition processes of NH3BH3-MAlH4 (M = Na, Li) composites were investigated by using thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS), powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses. We prepared the composites by ball-milling and the mixtures by hand-milling. The ball-milled composites desorbed 4-5 wt% hydrogen at three exothermic steps below 260 degrees C. The emissions of by-product gases, NH3, B2H6 and B3H6N3, were effectively suppressed. From XRD analysis, the formation of a mixed-metal (Na(Li), Al) amidoborane phase was suggested. Very different results were obtained using hand-milling. They showed only one exothermic reaction at 80-90 degrees C. The emission of by-product gases was not suppressed. By comparing the differences between ball-milled composites and hand-milled mixtures, the importance of mixed-metal amidoborane in this system was proposed.

• 出版日期2014