Near Ambient Condition Hydrogen Storage in a Synergized Tricomponent Hydride System

Reversible hydrogen storage over hydrides of light elements (HLEs) under ambient condition has been pursued actively for nearly two decades. However, because of unfavorable thermodynamics and/or severe kinetic barrier of HLEs, limited progress has been made. Here, it is demonstrated that the interaction of LiBH 4 with Mg(NH 2 ) 2 and LiH, three of the most investigated HLEs, can lead to a fully reversible dehydrogenation/rehydrogenation cycle at temperatures below 373 K. More importantly, with the desorption enthalpy of 24 kJ (mol H 2 ) −1 the dehydrogenation process at 1.0 bar H 2 is theoretically possible to be as low as 266 K. Characterization of this combination of HLEs shows that LiBH 4 serves as a reagent complexing with intermediates and products of the dehydrogenation of Mg(NH 2 ) 2 ‐LiH, and significantly alters the overall thermodynamic and kinetic properties of the system.