First-principles, data-guided screening and catalyst design: Unveiling energetic trade-offs in ammonia decomposition

Abstract

Ammonia decomposition is a promising route for CO2-free hydrogen production, but the development of efficient and cost-effective catalysts remains a challenge. Here, we employed a dual approach combining computational screening and free energy analysis to identify optimal catalysts, which were then validated experimentally. Pearson correlation coefficient analysis revealed a volcano-type relationship between NH3 dissociation energy (Ediss,NH3) and N2 adsorption energy (Ead,N2), highlighting Ru as the most effective monometallic catalyst. Reactor tests using supported Ru, Rh, Ir, Ni, and Co catalysts confirmed these predictions, with Ru exhibiting the highest NH3 conversion and a strong correlation between turnover frequency, activation energy (Ea), and electronic descriptors. Using this validated approach, we extended our analysis to bimetallic systems, identifying Ru-Ni alloys, as a promising alternative with balanced NH3 activation and N2 desorption. These findings demonstrate the effectiveness of combining computational and experimental methods to design high-performance NH3 decomposition catalysts. Further refinement of Ru-Ni alloy synthesis and structural control could enhance catalytic activity, supporting scalable hydrogen production. © 2025 Elsevier Inc.