Multi-Criteria selection of Metals-based electrocatalysts for electrochemical ammonia synthesis

The present study employed the Analytic Hierarchy Process (AHP), a renowned method for multi-criteria decision-making, to prioritize electrocatalysts for ammonia synthesis. This process considered the merits and demerits of both noble and non-noble metals electrocatalysts. The evaluation of seven parameters, including economic, lifetime, yield, selectivity, Faradaic efficiency (FE) and potentiometry, determines the justification of alternatives. In addition, there are seven types of electrocatalysts obtained from noble metals electrocatalysts, including Au, Pt, Ru, Rh, Pd, Ir, and Ag, as well as transition metal oxide (TMO), transition metal nitride (TMN), transition metal carbide (TMCA), transition metal chalcogenide (TMc), and other transition metal-based compounds (OTMB), and single atoms (SAs), derived from non-noble metals electrocatalysts, were considered as viable alternatives in light of the objective. According to the results of the multi-criteria evaluation, the criteria of yield, economic value, and lifetime had global weights of 0.306, 0.231, and 0.172, respectively, indicating their significance. Moreover, based on the criteria, Ru with a global weight of 0.189 and non-nobel metals SAs with a global weight of 0.214 are considered the most favored electrocatalysts for ammonia synthesis compared to both noble and non-noble electrocatalysts. The decision-making process considers economic justification (price), reaction yield, lifetime, FE, selectivity and potential as essential criteria, respectively. Ultimately, by closely considering the outcomes of individual atoms, the problems encountered by each catalyst can be effectively addressed, leading to impressive performance.