氢-氨绿色循环研究进展与展望

Green Hydrogen-Ammonia cycle refers to a promising chain for energy storage and transportation through the mutual conversion of hydrogen-ammonia. This cycle primarily includes Green Hydrogen to Ammonia (H2A) and Green Ammonia to Hydrogen (A2H). It aims to address the high energy consumption and excessive carbon dioxide emissions associated with the Haber-Bosch process for ammonia synthesis, while also tackling the challenges of hydrogen storage and transportation at high pressure within the hydrogen supply chain. Moreover, this cycle plays a vital role in connecting renewables, hydrogen, ammonia, and traditional industries such as iron and steel industry, promoting the efficient use of renewable resources. In the H2A phase, current research focuses on exploring new technologies, including catalysts, to synthesize ammonia under ambient conditions towards achieving industrial-scale production as an alternative to the Haber-Bosch method. However, challenges such as long-term stability still need to be addressed. To ensure the effective operation of the green cycle, the A2H must be efficient to split ammonia back into hydrogen for both direct and indirect uses, such as generating renewable electricity. A comprehensive understanding of ammonia synthesis and decomposition reactions is essential for a deeper insight into the Hydrogen-Ammonia cycle, as the H2A and A2H processes are reversible. In this review, we first explain the Hydrogen-Ammonia green cycle and then highlight the latest advancements in research on H2A and A2H driven by renewable energy under ambient conditions. Additionally, we endeavor to provide forward-looking insights into the future of the green Hydrogen-Ammonia cycle.