Construction and performance of an aluminum-water system for real-time hydrogen production in a severe cold environment
Guode Chen, Huihu Wang, Ziguan Zhang, Huang Xu, Hao Tu, Chenhuinan Wei, Xing Xiang, Zhixiong Xie
Abstract
To achieve real-time hydrogen delivery in a severe cold environment with temperatures between 253.15 K and 233.15 K, a unique aluminum-water system composed of Al-Ga-In-SnCl 2 (AGISc)/NaBH 4 /g-C 3 N 4 composite and CoCl 2 methanol solution are logically designed and constructed in this study. The final hydrogen generation from AGISc/NaBH 4 /1g-g-C 3 N 4 composite in a 0.04 M CoCl 2 methanol aqueous solution is 1185 mL·gAl −1 , and the conversion efficiency is 85.6% at 253.15 K. Even at 233.15 K, a 0.06 M CoCl 2 methanol aqueous solution may generate 1133 mL·gAl −1 of total hydrogen. With a maximum hydrogen generation rate (HGR) of 14 mL·gAl −1 ·s −1 and a conversion efficiency of 81.8%, real-time hydrogen production under extremely cold conditions is effectively possible. The microstructure and phase characterization of samples reveal that g-C 3 N 4 can facilitate mechanical alloying in the preparing process, while NaBH 4 can release a large amount of heat and create a mildly alkaline environment during hydrolysis, both of which enhance the hydrolysis activity. Moreover, CoCl 2 solvents in solution acting as the catalysts is essential to the reaction system by forming micro-cells of Al–Co or Al–Co 2 B.