Progress and challenges in energy storage and utilization via ammonia

Abstract Ammonia is a premium energy carrier with high content of hydrogen. However, energy storage and utilization via ammonia still confront multiple challenges. Here, we review recent progress and discuss challenges for the key steps of energy storage and utilization via ammonia (including hydrogen production, ammonia synthesis and ammonia utilization). In hydrogen production, we focus on important processes and catalytic designs for conversion of carbon feedstocks and water into hydrogen. To reveal crucial challenges of ammonia synthesis, catalytic designs and mechanisms are summarized and analyzed, in thermocatalytic synthesis, electrocatalytic synthesis and photocatalytic synthesis of ammonia. Further, in ammonia utilization, important processes and catalytic designs are outlined for ammonia decomposition, ammonia fuel cells and ammonia combustion. The goal of this review is to stimulate development of low-cost and eco-friendly ways for energy storage and utilization via ammonia.