Jiao Feng, Xu Bingjun
Center for Catalytic Science and Technology, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, 19716, USA.
Adv Mater. 2019 Aug;31(31):e1805173. doi: 10.1002/adma.201805173. Epub 2018 Dec 19.
Ammonia is a promising platform molecule for the future renewable energy infrastructure owing to its high energy density (when liquefied) and carbon-free nature. In particular, the interconversion between the chemical and electrical energies leveraging the nitrogen cycle could be an effective approach in mitigating the intermittency of renewable electricity production. However, efficient methods to store and release energy into and from ammonia, respectively, are still under development. Here, the latest developments in electrochemical ammonia synthesis and ammonia fuel cells are presented, and perspectives in the technical challenges and possible remedies are outlined. N electrolysis, plasma-enabled N activation, and electro-thermochemical looping are three potential approaches for electrochemical ammonia synthesis; however, achieving high selectivity and energy efficiency remains challenging. Direct ammonia fuel cells are suitable for a broad range of mobile and transportation applications but are limited by the lack of active catalysts for ammonia oxidation.
由于氨具有高能量密度（液化时）和无碳特性，它是未来可再生能源基础设施中一个很有前景的平台分子。特别是，利用氮循环实现化学能和电能之间的相互转换可能是缓解可再生电力生产间歇性的有效方法。然而，分别用于氨储能和释能的高效方法仍在研发中。本文介绍了电化学氨合成和氨燃料电池的最新进展，并概述了技术挑战及可能的解决方法。氮电解、等离子体辅助氮活化和电热化学循环是电化学氨合成的三种潜在方法；然而，实现高选择性和能源效率仍然具有挑战性。直接氨燃料电池适用于广泛的移动和运输应用，但受到氨氧化活性催化剂缺乏的限制。
