Theory-guided development of a barium-doped cobalt catalyst for ammonia decomposition

The efficiency of the catalytic decomposition of ammonia is a central challenge for the use of ammonia as a potential hydrogen vector and fuel for heavy-duty applications. In this study, we explore the promotional effect of alkali and earth-alkaline metals on cobalt and nickel catalysts for ammonia decomposition in a computational screening. We elucidate the strong influence of the recently proposed spin promotion effect on catalytic activity and identify barium as a promising and stable promoter of Co under the relevant reaction conditions. The predictions are validated experimentally through the study of a BaCo catalyst, ultimately yielding a metal-based hydrogen productivity of 12.2 mol g_Co⁻¹ h⁻¹ at 500 °C, common for state-of-the-art ruthenium catalysts. This work not only reports the successful development of a novel catalyst but also provides validation for the spin-promotion effect and its substantial influence on catalyst performance.