Ammonia Energy: Synthesis and Utilization

Ammonia is considered an excellent hydrogen storage medium, and its synthesis and utilization have received increasing attention. Here the recent advances and challenges in ammonia synthesis and utilization are reviewed and summarized. For the synthesis of ammonia, we describe the different methods, i.e., the Haber–Bosch method, the electrocatalytic method, the photocatalytic method, the plasma-assisted method, and the chemical looping method, and discuss their synthesis mechanisms. For the utilization of ammonia, we summarize ammonia as an excellent hydrogen carrier that produces COx-free hydrogen and is a zero-carbon energy source that can be used directly as a fuel. Moreover, the structure–performance relationships of catalysts in ammonia decomposition and hydrogen purification process have been explored in this section. Hopefully, this review will provide a detailed paradigm for ammonia synthesis and utilization and inspire the practical application of ammonia as energy.