2022 年 64 巻 2 号 p. 160-164
In recent years, a highly efficient ammonia decomposition catalyst using abundant metal such as Ni is strongly required for on-site hydrogen production. In this study, we clarify the role of Ca-N-H materials （e.g. CaNH, Ca（NH2）2, and Ca2NH） for Ni-based ammonia decomposition catalyst. Among these materials, CaNH significantly enhanced the ammonia decomposition performance of Ni catalyst. Ni/CaNH exhibited much greater ammonia decomposition activity than state-of-the-art Ni-based catalysts, and the operating temperature was reduced by ～100℃ than that of the oxide supported Ni-based catalysts. Detailed characterization and measurements revealed that ammonia decomposition reaction takes place at the site of NH2－ vacancy located at the Ni-CaNH interface.