Hydrides, Amides and Imides Mediated Ammonia Synthesis and Decomposition

Ammonia is feeding nearly half the world population and also holds the promise as a carbon-free energy carrier. The development of ammonia synthesis and decomposition processes under milder conditions is a grand challenge for more than a century. Increasing effort is devoted to this area in recent years and encouraging progress has been achieved. In this paper, we summarize our recent research using alkali or alkaline earth metal amides, imides and hydrides for ammonia synthesis and decomposition. These materials could serve as either indispensible component of active center in thermal catalytic process or nitrogen carrier for chemical looping ammonia synthesis. The synergy of amide, imide, or hydride with transition metals enables ammonia synthesis or decomposition with unprecedented high efficiency under milder reaction conditions, and thus opens an avenue to advance the chemistry or catalysis of N-2 fixation reaction. The compositional and structural diversity of the amide, imide and hydride materials provides plenty of opportunity and potential for further exploration and optimization.