Superior Dehydrogenation Performance of α-AlH3 Catalyzed by Li3 N: Realizing 8.0 wt.% Capacity at 100 °C
Shaolei Zhao1,2, Long Liang1,2, Baozhong Liu3
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Changchun, 130022, China.
Abstract:
The high dehydrogenation temperature of aluminum hydride (AlH3 ) has always been an obstacle to its application as a portable hydrogen source. To solve this problem, lithium nitride is introduced into the aluminum hydride system as a catalyst to optimize the dehydrogenation drastically, which reduces the initial dehydrogenation temperature from 140.0 to 66.8 °C, and provides a stable hydrogen capacity of 8.24, 6.18, and 5.75 wt.% at 100, 90, and 80 °C within 120 min by adjusting the mass fraction of lithium nitride. Approximately 8.0 wt.% hydrogen can be released within 15 min at 100 °C for the sample of 10 wt.% doping. Moderate dehydrogenation temperature slows down the inevitable self-dehydrogenation process during the ball-milling process, and the enhanced kinetics at lower temperature shows the possibility of application in the fuel cell.
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